Amir Public School (1) Biology 9th

& Science Academy Session: 2021-22

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1: - Define Science.
Ans: - In order to understand the principles, observations are made, experiments are done
and logical conclusions are drawn. Such studies are called science.
2: - Define life according to the science.
Ans: -Life is a set of characteristics that distinguish living things from non-living things. All of
these characteristics are found in each living things. There are more than 2 million
kinds of life on Earth that are known to scientists.
3: - Define Biology.
Ans: -Biology is the scientific study of life. The word “biology” has been derived from two
Greek words “bios” meaning “life” and “logos” meaning “thought or reasoning”.
4: - Define histology and cell biology.
Ans: - Histology: -The microscopic study of tissues is called histology.
Cell biology: -The study of the structures and functions of cells and cell organelles is
called cell biology.
5: - Define bio-geography, embryology and socio-biology.
Ans: -Bio-Geography: -It deals with study of the occurrence and distribution of
different species lf living organisms in different geographical regions of the world.
Embryology: -It is the study of the development of an embryo to new individual.
Socio-biology: -This branch deals with the study of social behaviour of the animals
that make societies.
6: - Define immunology and Entomology.
Ans: - Immunology: -It is the study of the immune system of animals, which defends
the body against invading microbes.
Entomology: -It is the study of insects.
7: - Define biophysics and biochemistry with examples.
Ans: -Biophysics: -It deals with the study of the principles of physics, which are applicable to
biological phenomena e.g. there is a similarity b/w the working principles of lever in
physics and limbs of animals in biology.
Biochemistry: -It deals with the study of chemistry of different compounds and
processes occurring in living organisms e.g. the study of basic metabolism of
photosynthesis and respiration involves the knowledge of chemistry.
8: - What is meant by Horticulture and forestry?
Ans: -Horticulture: -This profession includes the art of gardening. A horticulturist works for
the betterment of existing varieties and for the production of new varieties of
ornamental plants and fruit plants. This profession can be adopted after higher
secondary education.
Forestry: -In forestry, professionals look after natural forests and advises to the
government for planting and growing artificial forests. It can be adopted after higher
secondary education or after bachelor degree.
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Amir Public School (2) Biology 9th
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9: - Write contributions of Bu Ali Sina.
Ans: -Abdul Malik Asmai: -He is considered the first Muslim scientists who studies animals
in detail. His famous writings include “Al-abil”, “Al-Khail”, “Al-Wahoosh”, and “Kalq-al-
ansan”.
Bu-Ali-Sina: -He is honoured as the founder of medicine and called as Avicenna in the
West. He was a physician, philosopher, astronomer and poet. One of his famous books
“Al-Qanun-fi-al-tib” is known as the canon of medicine in West.
10: - Write down the levels of organization of a living organism.
Ans: - Subatomic particles make atoms and atoms make molecules. Different molecules
of life make organelles and different organelles assemble together to form the
simplest living unit i.e. the cell. Cells are organized in the form of tissues and different
coordinating tissues make an organ. Organs performing relative functions make
organs system and different organ systems make a complete individual. Then
population forms and after this a community is formed. In the end biosphere is
formed.
11: - What are bio-elements?
Ans: -Out of 92 kinds of elements that occur in nature, 16 are called bio-elements.
These take part in making the body mass of living organisms. Out of these elements,
Only six (O, C, H, N, Ca, & P) make 99% of the total mass.
Only ten (K, S, Cl, Na, Mg, Fe, Cu, Mn, Zn, & I) collectively make 01% of the total
mass.
12: - Define molecule and its types.
Ans: - Molecules: -In organisms, bio-elements usually do not occur in isolated
forms rather they combine through ionic or covalent bonding. The stable particle
formed by such bonding is called as molecule or bio-molecule. It is two types.
i. Micro-molecules: - Micro-molecules are with low molecular weight e.g. glucose,
water etc.
ii. Macromolecules: -Macromolecules are with high molecular weights e.g. starch,
proteins etc.
13: - Define biotechnology.
Ans: - It deals with the practical application of living organisms to make substances for the
welfare of mankind. (For example take help of your teacher)
14: - Write down the function of mitochondria and ribosomes.
Ans: - Mitochondria are specialized for cellular respiration and ribosomes are specialized for
protein synthesis.
15: - Write biological name and importance of mustard plant.
Ans: - Its biological name is “Brassica Campestris”. The plant body is used as vegetable and
its seeds are used for extracting oil.
16: - Define Morphology and physiology.
Ans: - Morphology: -This branch deals with the study of form and structures of living organisms.
Physiology: -This branch deals with the study of the functions of different parts of
living organisms.
17: - Define population and community level
Ans: - Population level: -A population level is defined as a group of organism of the same species
located at the same place, in the same time e.g. no. of students in biology class in 2010.
Community level: -A community is an assemblage of different populations,
interacting with one another within the same environment e.g. a forest.
18: - Write down the types of cellular organizations.

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Ans: - Unicellular: -In unicellular organisms only one cell makes the life of an organism. All
the activities carried out by the only cell e.g. Amoeba etc.
Colonial cellular: -In colonial type of cellular organization many unicellular
organisms live
together but do not have any division of labour among them e.g. Volvex.
Multicultural:-In multicellular organizations cells are organized in the form of
tissues, organs and organ systems e.g. Frog and mustard plant.
19: - What are vegetative and reproductive parts of mustard plant?
Ans: - Vegetative parts. The parts which don’t take part in sexual reproduction are called
vegetative parts e.g. root, stem, branches and leaves.
Reproductive parts: -The parts which take parts in sexual reproduction are called
reproductive organs e.g. flower.
20: - Define parasitology and parasite.
Ans: - Parasitology: -This branch deals with the study of parasites. The structure, habitats,
mode of transmission, life histories and host-parasite relationships are studied in this
branch.
Parasite: -Parasites are the organisms that take food and shelter from living hosts
and, in return, hard their lives.
21: - Define taxonomy and microbiology.
Ans: - Taxonomy: -It is the study of the naming and classification of organisms into groups
and subgroups.
Microbiology: -It deals with the study of microorganism such as bacteria etc.
22: - What are prokaryotes and eukaryotes.
Ans: - Prokaryotes: -The unicellular organisms that don’t have distinct nucleus are grouped
as prokaryotes e.g. bacteria.
Eukaryotes: -The unicellular or simple multi-cellular organisms that have distinct
nucleus grouped as eukaryotes e.g. Euglena.
23: - Define molecular biology.
Ans: - This branch deals with the study of the molecules of life e.g. water, proteins,
carbohydrates, lipids and nucleic acid.
24: - What is animal husbandry?
Ans: -It is the professional study of the diagnoses and treatment of diseases of the livestock.
The livestock includes all the domestic animals. It can be adopted after higher
secondary education.
25: - What are the major biological issues today?
And: - Human population growth, infectious diseases, addictive drugs and pollution are the
major biological issues today.
26: - Name any four unicellular organisms.
Ans: - Amoeba, Paramecium, Euglena, Chlymadomonas

1: - What is scientific method?

Ans: - Science is the systemized knowledge derived from observations and experiments
carried out to determine the principles about how the nature operates. Many
scientists use a method to make and test new theories, is called scientific method.
2: - What is biological method? Write a brief on its progress.
Ans: -Biological method: -The scientific method, in which biological problems are
solved, is termed as biological method.
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Progress: -It has played an instrumental part in scientific research for almost 500
years. From Galileo’s experiment back in the 1590s to current research, the biological
method has contributed to the advancements in medicines and technology.
3: - What is hypothesis?
Ans: - Biologists organizes his/her and other’s observations into data form and constructs a
statement that may prove to be the answer of the biological problems under study.
This tentative explanation of the observations is called hypothesis.
4: - Write down the characteristics of a well-defined hypothesis.
Ans: - 1. It should be a general statement.
2. It should be a tentative idea.
3. It should agree with available observations.
4. It should be kept as simple as possible.
5: - What is deduction.
Ans: - In the biological method, if a particular hypothesis is true then one should expect
(Deduction) a certain result. Deductions are also drawn by using inductive and
deductive reasoning.
6: - What are controlled experiments?
Ans: - An experiment in which the competition b/w a controlled group and experimental
group is tested is known as controlled experiments.
Explanation: -In an experiment to test the necessity of carbon dioxide for the
photosynthesis, one can contrast the control group (a plant with freely available CO2
with an experimental group (a plant which no CO2 available). The necessity of CO2 will
be proved when photosynthesis occurs in the control group and doesn’t occur in the
experimental group.
7: - Write a brief note on the history of malaria.
Ans: - In ancient time (more than 2000 years ago), physicians were familiar with the
disease. They described it as a disease of chills and fevers with reoccurring attacks.
They also observed that the disease was more common among people living in low,
marshy areas. It was thought that the stagnant water of marshes poisoned the air and
as a result of breathing in this “bad air” people got malaria. This belief led to the name
of the disease. The Italian word “mala” means “bad” and “aria” means “air”.
8: - Write the pathogen of malaria.
Ans: - This disease spreads through a germ “plasmodium” present in the body of female
mosquito “Anopheles”.
9: - What are observation? Also write its types.
Ans: - Observation: -In observation, biologists deeply observe anything to solve biological
problem and search the answers of questions which are arising in their minds.
Qualitative Observations: -An observation in which the quality or nature of a thing is
discussed is called qualitative observation e.g. A liter of water is heavier than a liter of
ethanol.
Quantitative observations: -An observation which is discussed in the form of digits
is called quantitative observation e.g. a liter of water weighs 1000 grams and a liter of
ethanol weighs 789 grams.
10: What do you know about Culex?
Ans: - It is type of female mosquito. Ross used it is his experiment. He allowed a female Culex
mosquito to bite on the sparrows suffering from malaria.
11: - Write about the welts due to inject of a mosquito.
Ans: - When a female mosquito pierces the skin with her mouthparts, she injects a

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small amount of saliva into the wound before drawing food. The welts that appears
after the mosquito leaves is not a reaction to the wound but an allergic reaction to the
saliva.
12: - What is theory?
Ans: - When a hypothesis is given a repeated exposure to experimentation and is not
falsified, it increases biologists’ confidence in the hypothesis. The hypotheses that
stand the test of time are called theories.
13: - Define law or principle.
Ans: - Productive theories keep on suggesting new hypotheses and so testing goes on. If
a theory survives such doubtful approach and continues to be supported by
experimental evidence, it becomes a law or principle.
14: - How data is organized by scientists?
Ans:- Data is organized in different formats like.
1. Graphics 2. Tables 3. Flow charts 4. Maps 5. Diagrams
15: - What are bioinformatics?
Ans: - Bioinformatics refers to the use of algorithms, computational and statistical
techniques for the analysis of biological data.
16: - What is computational biology?
Ans: - Computational biology refers to hypothesis-driven investigation of a specific biological
problem using computers.
17: - Mathematics is a necessary component of biological method. How?
Ans: - Biological method also involves the use of applied mathematics to solve biological
problems. Its uses are following.
1. Gene finding 2. Protein structure
3. protein-protein interactions 4. Modeling of evolution
18: - What do you know about cinchona, quinine and “quina-quina”?
Ans: - Quina-Quina: -It was the bark of a tree which was very suitable for curing fevers. It
was from America.
Cinchona: -Some dishonest merchants began to substitute the bark of another tree,
the cinchona. It was closely resembled quina-quina. It was found to be an excellent for
treating malaria.
Quinine: -Cinchona bark contains a chemical that is quinine. It is very effective in
treating the disease of malaria.
19: - How plasmodium is entered in man’s body?
Ans: - We know mosquitoes transmit plasmodium. When mosquito bites a patient of malaria
then plasmodium transmits into its body and when this mosquito bites the healthy
man then the plasmodium transmits into the healthy man.
20: - Write the experiment by Ronald Ross on Sparrows.
Ans: - See Text book Page #25
21: - Write down the contribution of A. F. king.
Ans: -In 1883, A. F. King presented 20 observations which proved very useful to know the
reason of the disease of malaria. He presented a hypothesis on the bas of these
observations that “Mosquito transfer plasmodium which is responsible of malaria.
22: - And Tell why quantitative observations are better than qualitative
observations?
Ans: - Quantitative observations are considered more accurate than qualitative ones
because the former are invariable and measurable and can be recorded in terms of
numbers.

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Amir Public School (6) Biology 9th
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1: - What is biodiversity?
Ans: - Biodiversity is a measure of the variety of organism present in different ecosystems. It
is derived from two words i.e. “Bio” and “diversity”. Formerly it was called “natural
diversity”.
2: - On which factors biodiversity depend?
Ans: - Diversity depends upon climate, altitude, soils and the presence of others species. It is
not distributed evenly on Earth. It is richer in the tropics while there are fewer species
in the polar regions.
3: - Define class and order.
Ans: - Class:-A class is a group of related orders.
Order:-An order is a group of related families.
4: - Write a brief note on the importance of biodiversity.
Ans: - Biodiversity provides food for humans. A significant proportion of drugs are derived,
directly and indirectly, from biological sources. A wide range of industrial materials
e.g. building materials, fibers, dyes, resins, adhesives, rubber and oil are derived
directly from biological resources.
5: - Define classification and write down its purposes.
Ans: - A process in which biologists classify the organism into groups and subgroups is
called classification.
Purposes: - 1. To determine similarities and differences among organism
so that they can be studies easily.
2. To find the evolutionary relationships among organisms.
6: - Write down the classification of pea plant.
Ans: - See Text Book Page#34
7: - What is the base of classification?
Ans: - Classification based on relation’s b/w organisms Biologists have classified all
the known organisms into groups and subgroups on the basis of similarities. These
similarities are seen in structures, biochemistry, cytology and genetics. The basic unit
of classification is “species”.
8: - What is meant by taxonomic hierarchy?
Ans: - The groups into which organisms are classified are known as taxonomic categories or
taxa and these taxa form a ladder, called taxonomic hierarchy. The biggest “taxon” of
taxonomy is kingdom and smallest is species. Its detail is as follow.
1. Phylum 2. Class 3. Order 4. Family 5. Genus 6. Species
9: - Define species.
Ans: - A species is a group of organisms which can interbreed freely among them and
produce fertile offspring.
10: - What is cross-breed?
Ans: - The reproduction between two different but closely related species is called cross-
breed. e. g. cross breed b/w male donkey and female horse produces fertile offspring
11: - Write a brief note on the history of classification.
Ans: - 1. First of all, the Greek philosopher Aristotle classified all living organism known at
that time as either in the group “plants” or in “animals”.
2. In 700s, Abu-Usman Umer Aljahiz described the characteristics of 350 species of
animals in his book.
3. In 1172, Ibn Rushd, who was a judge in Seville, translated and abridged Aristotle’s
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book “De Anima” into Arabic. His original commentary is lost, but its translation into
Latin is available.
4. Modern classification was introduced by Carolus Linnaeus, who grouped species
according to similar physical characteristics.
12: - Define autotrophs and hetrotrophs.
Ans: - Autotrophs: -Organisms which can prepare their food themselves are called
autotrophs. They are placed in kingdom plantae.
Heterotrophs: -Organisms which can’t prepare their food instead relay on autotrophs
are called heterotrophs. They are placed in kingdom Animalia.
13: - How do you divide five kingdom systems on the basis of cells?
Ans: - Organisms having prokaryotic cells have been placed in Monera kingdom whereas
organisms having Eukaryotic cells have been placed in kingdom Protista, Fungi,
Plantae and Animalia.
14: - What is binomial nomenclature?
Ans: - Binomial nomenclature is the method of giving scientific names to living organisms.
The scientific name of a species consists of two names: the first is the genus name and
the second one is the name of the species. Scientific names are usually printed italic,
when handwritten they are underlined.
15: - Write down the importance of binomial nomenclature.
Ans: - The value of this system is due to its widespread use and the stability of its names. In
binomial nomenclature, every species can be unambiguously identified with just
two words. The same name can be used all over the world, in all languages, avoiding
difficulties of translation.
16: - How Algae resemble plants?
Ans: - Algae has cell wall and chlorophyll as well in chloroplast. This is why they resembles
with plants.
17: - What are simple multi-cellular organisms?
Ans: - Organisms which don’t have multi-cellular sex organs and don’t form embryos during
their life cycle are called simple multi-cellular organisms.
18: - Define endangered species. Also write some examples.
Ans: - A species is called endangered when it is at risk of extinction in near future.
Examples: -Indus Dolphin, Marco Polo Sheep, Houbara Bustard.
19: - Define extinct species and give some examples.
Ans: -Extinct species: -A species is called extinct when there is no doubt that the last
individual of that species has died.
Examples: -Lion, tiger, Asiatic cheetah, Indian one-horned rhinoceros, swamp deer,
Indian wild ass, hangul, blackbuck etc.
20: - Write down the causes of deforestation.
Ans: - The race to produce cash through fruits, spices, sugar, tobacco, soap, rubber, paper
and cloth has stimulated many to get them by using oil and by destroying the forests.
Deforestation can be the result of deliberate removal of forests for wood, agriculture
or urban development.
21: - Write down the effects of man on biodiversity.
Ans: - 1. Habitat loss and deforestation 2. Over-hunting.
3. Introduction of new species 4. Domino effects
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5. Pollution 6. Climate change
22: - Write down the organizations which are working for the conservation of
biodiversity.
Ans: - 1. IUCN (International Union for the conservation of Nature and natural Resources.
2. WWF-P (World Wildlife Fund-Pakistan)
23: - Write down the name of national bird and national animal of Pakistan.
Ans: - Markhor is the national animal of Pakistan. Chakor patridge is the national bird of
Pakistan.
24: - How do you compare between kingdom plantae and Animalia.
Ans: - Kingdom Plantae includes eukaryotic multicellular autotrophs. They are autotrophic
in nutritional mood. They have multicellular sex organs. Whereas in kingdom
Animalia includes eukaryotic multicellular consumers. They lack cell walls and show
movement.
25: - Write down the properties of kingdom monera.
Ans: - It includes prokaryotic organisms i.e., they are made of prokaryotic cells. They are
unicellular, although some types form chains, clusters, or colonies of cells. Within this
kingdom, there are two different kinds of organisms i.e. bacteria and cyanobacteria.
26: Give characteristics of Sea Star. OR Write a note sea star.
Ans: - Sea star means star fish. It eats mussels. If sea stars are removed from a region in
ocean, mussels rapidly increase in number. Large numbers of mussel’s prey on small
animals and become dangerous for their existence.
27: - Describe the two characteristics of kingdom plantae.
Ans: - i. It includes autotrophic in nutritional mode, making their own food by
photosynthesis.
ii. They have multicellular sex organs.
28: - Differentiate b/w prions and viroids.
Ans: - Both are A-cellular particles. Prions consist of proteins only whereas viroids consist of
RNA only

1: - What is magnification and resolution or resolving power?

Ans: - These both terms are used in microscopy.
Magnification: -Magnification is the increase in the apparent size of an object and it is
an important factor in microscopy.
Resolution or resolving power: -Resolution is the measure of the clarity of an
image. It is the minimum distance at which two objects can be seen as separate
objects.
2: - What is meant by the resolution of human eye?
Ans: - The human naked eye can differentiate between two points, which are at least 0.1 mm
apart. This is known as the resolution of human eye.
3: - Write down the types of microscopes.

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Ans: - Light microscope: -A light microscope can magnify objects only about 1500 times
without causing blurriness i.e. its magnification is 1500X. Its resolving power is 0.2
1
micrometer. 1 micrometer is equal to mm.
1000
Electron microscope: -The E. M has much higher resolving power than L.M. The most
modern EM can distinguish objects as small as 0.2 nm which is equal to the
1
mm.
1000,000
4: - Write down the types of electron microscope.
Ans: - Transmission electron microscope: -It is used to study the details of the internal
cell structure. The TEM magnify objects about 250,000 times.
Scanning electron microscope: -In SEM, electrons are reflected from the metal-
coated surfaces. SEM is used to study the structure of cell surfaces.
5: - What is meant by microscopy and tell where and when first microscope was
made?
Ans: - The use of microscope is termed is microscopy.
The first microscope was developed by Zacharies Janssen of Holland in 1595.
6: - Define epithelial tissues and write down its types.
Ans: - Epithelial tissues covers the outside of body and lines organs and cavities. The cells in
this tissue are very closely packed together. Its types are following.
i. Squamous epithelial. ii. Cuboidal epithelial.
iii.Columnar epithelial. iv. Ciliated Columnar epithelial.
v. Stratified squamous epithelial.
7: - Differentiate between cell membrane and plasma membrane.
Ans: - Cell membrane: -When we talk about all the membranes of a cell, we say them as cell
membrane.
Plasma membrane: -When we talk about only the outer membrane of the cell, we say
it as plasma membrane.
8: - What is semi permeable membrane?
Ans: - Cell membrane as a fence which allows a very few molecules across it while fencing
the majority of chemicals inside the cell, is called semi permeable membrane.
9: - Write a brief note on layers of cell wall and the chemicals present in it.
Ans: - The outer layer of the plant cell wall is known as primary cell wall and cellulose is the
most common chemical in it. Some plants cells for example xylem cells also have
secondary wall on the inner side of the primary cell wall. It is much thicker and lignin
and other chemicals are embedded in it. Chitin is present in the cell wall of Fungi and
peptidoglycan is present in the cell wall or prokaryotes.
10: - Write a brief note on cytoplasm.
Ans:- Cytoplasm is defined as the material between the plasma membrane and nuclear
envelope. It is a semi-viscous and semi-transparent substance. It contains water in
which many organic (proteins, carbohydrates, lipids) and inorganic salts are
completely or partially dissolved. It provides space for the proper functioning of the
organelles.
11: - What is cytoskeleton?
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Ans: - The cytoskeleton is an important, complex and dynamic cell component. It is invisible
under LM. It maintains the cell’s shape, anchors organelles in place and moves parts or
the cell in processes of growth and motility. There are many types of filaments that
make up it.
12: - What is nuclear envelope and nucleoplasm?
Ans: - Nuclear envelope: -The nucleus is bounded by a double membrane known as nuclear
envelope.
Nucleoplasm: -Inside the nuclear envelope a granular matrix is present is called
nucleoplasm.
13: - Write a note on Xylem and Phloem.
Ans: - Xylem Tissue: -Xylem tissue is responsible for the transport of water and dissolved
substances from roots to the aerial parts. Due to the presence of lignin, the secondary
walls of its cells are thick and rigid. That is why xylem also provide support to plant
body. Two types of cells are found in xylem.
i.Vessel elements ii. Tracheids.
Phleom Tissue: -Phleom tissue is responsible for the conduction of dissolved organic
matter b/w different parts of plant body. Phloem tissue contains sieve tube cells and
companion cells. Sieve tube cells are long and their end walls have small pores. Many
sieve tube cells join to form long sieve tubes. Companion cells make proteins for sieve
tubes.
14: - Write a brief note on ribosomes.
Ans: - Ribosomes are tiny granular structures that are either floating freely in the cytoplasm
or are bound to the endoplasmic reticulum. Each ribosome is made up of almost equal
amount of proteins. It plays a vital role in preparing proteins.
15: - What is thylakoids?
Ans: - In plastids, chloroplast is bounded by a double membrane. The membrane is smooth
while the inner membrane gives rise to sacs called thylakoids.
16: - Write down the types of plastids.
Ans: - 1. Chloroplasts: -Chloroplasts are the sites of photosynthesis in eukaryotes. They
contain chlorophyll, the green pigment necessary for photosynthesis, and associated
accessory pigments.
2. Chromoplasts: -They contain pigments associated with the bright colours and are
present in the cells of flower petals and fruits. Their function is to give colour to these
parts and thus help in pollination and dispersal of fruit.
3. Leucoplasts: -They are the third type of plastids. They are colourless and store
starch, proteins and lipids. They are present in the cells of those parts where food is
stored.
17: - Differentiate between rough and smooth endoplasmic reticulum.
Ans: - Rough Endoplasmic Reticulum: - RER is so-named because of its rough appearance
due to the numerous ribosomes that are attached to it. Due to the presence of
ribosomes, RER serves a function in protein synthesis.
Smooth endoplasmic reticulum: -SER lacks ribosomes and is involved in lipids
metabolism and in the transport of materials from one part of the cell to the other. It
also detoxifies the harmful chemicals that entered the cell.
18: - What are centrioles?
Ans: - Animals and many unicellular organisms have hollow and cylindrical organelles
known as centrioles. They are made of nine triplets of microtubules that are composed
of an important protein, known as tubulin.

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19: - What are Golgi complex and Golgi vesicles?
Ans: - Golgi complex: -A set of flattened sacs that are stacked over each other. Golgi named
this set of cisternae as Golgi apparatus. It is also called Golgi body or Golgi complex
and is found in both plant and animal cells.
Golgi vesicles: -Golgi complex modifies molecules coming from RER and packs them
into small membrane bound sacs called Golgi vesicles.
20: - Differentiate between prokaryotic and eukaryotic cells.
Ans: - In eukaryotic cell there is a prominent nucleus and many membrane-bound
organelles, which are not present in prokaryotic cell. The DNA of prokaryotic cell
floats in cytoplasm near the centre: the DNA of eukaryotic cell is held within the
nucleus. Eukaryotic cell is ten times the size of prokaryotic cell.
21: - What is meant by open system of cell?
Ans: - It means that a cell takes in substances needed for its metabolic activities through its
cell membrane. Then it performs the metabolic processes assigned to it. Products and
by-products are formed in metabolism.
22: - Define diffusion, facilitated diffusion, osmosis and reverse osmosis.
Ans: - Diffusion: -Diffusion is the movement of molecules from an area of higher
concentration
to the area of the lower concentration i.e. along concentration gradient.
Facilitated diffusion: - The type of diffusion which takes place with the help of carrier
proteins are called facilitated diffusion.
Osmosis: -Osmosis is the movement of water across a semi permeable membrane
from a solution of lesser solute concentration to a solution of higher solute
concentration.
Reverse osmosis: -It is a type of osmosis in which semi-permeable membranes
efficiently separate salts from water under pressure.
23: - What is tonicity of solution theory?
Ans: -The term tonicity refers to the relative concentration of solutes in the solutions being
compared.
1. Hypertonic solution: -They are those solutions in which more solute is
present.
2. Hypotonic solution: -They are those solutions with less solute.
3. Isotonic solutions: -They have equal concentrations of solutes.
24: - What is Turgor and Turgor pressure?
Ans: - Turgor: - The cell wall prevents over-expansion of the cell by exerting an inwardly
directed or an opposing pressure which prevents the entry of more water into the cell.
The condition thus produced in the cell is called Turgor.
Turgor pressure: - In turgid plant the internal pressure exerted on the cell wall is
called turgor pressure.
25: - Define filtration and active transport.
Ans: - Filtration: -Filtration is a process by which small molecules are forces to move across
semi-permeable membrane with the aid of hydrostatic pressure of blood pressure.
Active transport: -Active transport is the movement of molecules from an area
of lower concentration to the area of higher concentration. This movement against the
concentration gradient requires energy in the form of ATP.
26: - What is endocytosis and exocytosis?
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Ans: - Endocytosis: - It is the process of cellular ingestion of bulky materials by the enfolding
of cell membrane. It is of two types.
i. Phagocytosis ii. Pinocytosis
Exocytosis: -It is the process through which bulky material is exported.
27: - Write a note on nervous tissues.
Ans: - Nervous system forms a communication system and performs this task. This tissue is
mainly composed of nerve cells or neurons, which are specialized to conduct messages
in the form of nerve impulses. Nervous tissue is found in brain, spinal cord and nerves.
28: - Define simple tissue and write down its types.
Ans: - The tissues which are made of single type of cells, are called simple tissues. They are
of two types.
1.Meristematic Tissue: -These tissues are composed of cells, which have the ability to
divide. The cells are thin walled, have large nucleus and small or no vacuoles. They
don’t have inter-cellular spaces among them. Two main types of meristematic tissues
are recognized in plants.
i.Apical meristerms ii.Lateral meristems
2. Permanent Tissues: -Permanent tissues originate from meristematic tissue.
The cells of these tissues don’t have the ability to divide. They are further classified
into following types.
i. Epidermal tissues ii. Ground tissues iii. Support tissues
29: - What is fluid mosaic model?
Ans: - According to this model, there is a lipid bilayer in which the protein molecules are
embedded. The lipid bilayer gives fluidity and elasticity to membrane. Small amount of
carbohydrates are also found in cell membrane. These are joined with proteins or
lipids of membrane.
30: - Differentiate b/w Columnar epithelial and ciliated columnar epithelial.
Ans: - Columnar epithelial has elongated cells. It is found in alimentary canal, gall bladder
etc. where it makes secretions whereas ciliated columnar epithelial had elongated
cells with cilia. It is present in trachea and bronchi and propels mucous.
31: -What is Lysosomes?
Ans: - Lysosomes are single-membrane bound organelles. It contains strong digestive
enzymes and work for the breakdown of food and waste materials within cell.
32: - Define cell wall. Ans also tell in which organisms is it present?
Ans: - Cell wall is a non-living and strong component of cell, located outside plasma
membrane. It is present in Prokaryotes and plants like protists.
33: - Give functions of cell membrane.
Ans: - Cell wall maintains the internal composition of cell. In addition to this vital role, cell
membrane can also sense chemical messages and can identify other cells.
34: - Describe functions of vacuoles in a cell.
Ans: - Cells have many small vacuoles in their cytoplasm. They help to turgid the cell and
many cells take in materials from outside in the form of food vacuole and then digest
the material with the help of lysosomes. Some unicellular organisms use contractile
vacuole for the elimination of wastes from their bodies.
35: - Write the structure of mitochondria.
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Ans: - Mitochondria are double membrane-bonded structures found only in eukaryotes. The
outer membrane of a mitochondrion is smooth but the inner membrane forms many
infoldings, called cristae. Mitochondria have their own DNA and ribosome.
36: - Write down the principles of the modern cell theory.
Ans: - 1. All organisms are composed of one or more cells.
2. Cells are the smallest living things, the basic unit of organization of all organisms.
3. Cells arise only by divisions in previously existing cells.
37: - What is meant by plasmodesmata?
Ans: - There are pores in the cell walls of adjacent cells, through which their cytoplasm is
connected. These pores are called Plasmodesmata.

1: - What is reproduction?
Ans: - The production of new structures and individuals similar to the existing structures
and individuals is called reproduction.
2: - What is cell cycle? Write down its steps.
Ans: - The cell cycle is the series of events from the time a cell is produced until it completes
mitosis and produces new cells.
1. Interphase 2. Mitotic phase or M-phase.
3: - What is mitosis? Write its steps.
Ans: - Mitosis is the type of cell division in which a cell divides into two daughter cells, each
with the genetic equivalent of the parent cell i.e. same number of chromosomes as
were present in the parent cell. It has two steps.
1. Karyokinesis 2. Cytokinesis
4: - What are somatic and germ cells?
Ans: - Somatic cells are those which are forming the body of organism while germ line cells
are those which give rise to gametes.
5: - What is open and closed mitosis?
Ans: - Open mitosis: -In common mitosis, nuclear envelope disappears and spindles are
formed inside the cytoplasm. It is called open mitosis.
Closed mitosis: -Fungi and some protists undergo a variation called closed mitosis,
where the spindle forms inside the nucleus.
6: - What are kinetochore fibers?
Ans: - When the spindle grows to sufficient length, some of the spindle fibers, known as
kinetochore fibers, begin searching for kinetochores to attach.
7: - What is phragmoplast?
Ans: - Cytokinesis in plant cells occurs differently. Vesicles derived from the Golgi apparatus
move to the middle of the cell and fuse to form a membrane-bounded disc called the
cell plate or phragmoplast.
8: - What is budding in Hydra?
Ans: - Hydra reproduces asexually by budding. During this process mitosis forms a mass
of cells called bud on the surface of hydra. The mitosis continues in the cells of the bud
and it grows into a new individual.
9: - What is meant by gene mutation?
Ans: -Alternative forms of a gene arise by a sudden change in the structure of a gene. This
change is called gene mutation.
10: - What are tumors? Write down its types.

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Ans: - Sometimes mutations occur in genes and the cells continue to divide. It results in
growths of abnormal cells called tumors.
1. Benign tumor: -As long as the tumors remain in their original location, they are
called benign.
2. Malignant or Cancerous tumor: -When tumors invade other tissues, they are
called malignant or cancerous tumors.
11: - What is metastasis?
Ans: - A processes in which cell of disease invade other tissues of body is called metastasis
means spreading of disease.
12: - What is meant by cleavage furrow?
Ans: - In animal’s cells, Cytokinesis occurs by a process known as cleavage. A cleavage
furrows develops where the metaphase used to be.
13: - What is meiosis?
Ans: The word meiosis comes from the Greek “meioun” meaning “to make smaller”,since it
results in a reduction in chromosomes number. Or you can say that meiosis is the
process by which one diploid eukaryotic cell divides to generate four haploid
daughters’ cells. The numbers of chromosomes remain half.
14: - What are unique characters in meiosis?
Ans: - 1. Pairing b/w homologous chromosomes 2. Genetic recombination
15: - What are bivalent chromosomes?
Ans: - In the prophase I of meiosis, the homologous chromosomes line up with each other
and form pairs. The combined homologous chromosomes are said to be bivalent
chromosomes.
16: - What are diploid and haploid cells?
Ans:- Diploid cells: -Diploid means the cells in which chromosomes are in pairs
(homologous pairs).
Haploid cells: -Haploid means the cells with half the number of chromosomes i.e.
chromosomes are not in the form of pairs.
17: - What is chiasmata and synapsis?
Ans: - The two non-sister chromatids of homologous chromosomes become “zipped”
together, forming complexes known as chiasmata; this process is known as synapsis.
18: - What is crossing-over?
Ans: - During prophase I of meiosis, when the non-sister chromatids of homologous
chromosomes randomly exchange their segments and the phenomenon is knows as
crossing over.
19: - Write down the importance of meiosis according to August weisemann.
Ans: - In 1890, August Weismann described that meiosis was necessary to transform one
diploid cell into four haploid cell if the number of chromosomes had to be maintained.
The meiosis also necessary for variation in neat generation.
20: - What is binary fission?
Ans: - Binary fission means division of a cell into two cells. So, when prokaryotic cells pass
through a cell division like mitosis, then it is called binary fission.
21: - What is alternation of generation in plant cycle?
Ans: - Plants’ life cycle shows alternation of generation. The cells of the diploid sporophyte
generation undergo meiosis to produce haploid spores, which grow into haploid
gametophyte generation. The haploid gametophyte generation produces haploid
gametes through mitosis.
22: - What is meant by disjunction and non-disjunction?

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Ans: - It is an error of meiosis. The normal separation of chromosomes or sister chromatids
in meiosis is termed as disjunction. When the separation is abnormal, it is called non-
disjunction.
23: - What is apoptosis?
Ans: - Apoptosis is one of the main types of programmed cell death, and involves a series of
biochemical events. This is controlled by exteracellular signals or intracellular signals.
Apoptosis can occur then a cell is damaged or under goes stress conditions.
24: - What is necrosis?
Ans: - Necrosis is the name given to accidental death of cells and living tissue. Necrosis is less
sequential than apoptosis. Necrosis may occur when a cell is given hypoxic
environments.
25: - What is meant by blebs and apoptotic bodies?
Ans: - Blebs: -The cell membrane shows irregular buds known as blebs, through which the
cellular components are discharge.
Apoptotic bodies: -The blebs broken off from the cell are called apoptotic bodies,
which are then phagocytosed by other cells.
26: - Define Karykinesis and also write down its types.
Ans: - The division of nucleus is called karykinesis. It has four steps.
i. Prophase ii. Metaphase iii. Anaphase iv. Tleophase
27: - The S-phase of interphase is important and a cell can never divide without it.
Justify?
Ans: - Because In this phase the cell duplicates its chromosomes. The DNA molecules of each
chromosomes are copied, and new protein molecules are attached. No daughter cell
has normal number of chromosomes without duplication of chromosomes.
28: - What is meant by G “0” phase?
Ans: - Cells that have temporarily or permanently stopped dividing are said to have entered
a state of quiescence, called G O phase.
29: - How Cytokinesis in the cells of plants is different from the cells of animals.
Ans: - Cytokinesis in plant cells occurs differently. Vesicles derived from the Golgi apparatus
move to the middle of cell and fuse to form a membrane-bounded disc called cell plate
or phragmoplast. The process takes place in plant cell. While the division of animal cell
takes place by cleavage furrow and cut down the cell from central position.
30: - Write stages of interphase.
Ans: - Interphase is further divided into three phases i.e
i. G I Phase ii. S Phase iii. G II Phase
31: - Define interkinesis.
Ans: - After meiosis I both haploid daughter cells enter a period of rest known as interkinesis
or interphase II.
32: - How metaphase plate is formed?
Ans:- Two kinetochore fibers from opposite poles attach each chromosome. Chromosomes
arrange themselves along the equator of cell forming a metaphase plate.

1: - Define metabolism and its types.

Ans: - Metabolism is the set of biochemical reactions that occur in living organisms in order
to maintain life. This term is derived from Greek word meaning “change”.

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The concept of metabolism was first of all given by Ibn-e-Nafees, who stated that “the
body and its parts are always undergoing change.
i. Anabolism: -Anabolism is the total series of chemical reactions involved in the
synthesis of compounds. Energy is used in this process.
ii.Catabolism: -Catabolism is the series of chemical reactions that breakdown larger
molecules. Energy is released in this process.
2: - Define enzymes and substrates.
Ans: Enzymes: - Enzymes are proteins that catalyze biochemical reactions and are not
changed during the reaction. In 1878, German physiologist Winhelm Kuhne first used
the term enzyme.
Substrate: -The molecules at which enzymes act are called substrates.
3: - How enzymes are used to lower activation energy?
Ans: - i. Altering the shape of the substrates and reducing the amount of energy required to
complete the transition.
ii. Disrupting the charge distribution
iii. Bringing substrates in the correct orientation to react.
4: - What is active site?
Ans: - The activities of enzymes are determined by a small portion of the enzyme’s molecule
which is directly involved in catalysis. This catalytic region, known as active site.
5: - What is cofactor in enzymes? Explain its types.
Ans: - Some enzymes need non-protein molecules or ions to show full activity, are called
cofactors. These can be either inorganic or organic.
Prosthetic groups: - If organic cofactors are tightly bound to enzyme, they are called
prosthetic groups.
Co-enzymes: -If organic cofactors are loosely attached with enzyme, they are called
co-enzymes.
6: - Write down few important co-enzymes and their uses.
Ans: - Important co-enzymes: -
1. Riboflavin 2. Thiamine 3. Folic acid
Uses: - 1. In food industry 2. In brewing industry
3. In paper industry 4. In biological detergent
7: - Write down the factors affecting the speed of enzymes action.
Ans: - 1. Tempertaure 2. Substrate concentration 3. pH
8: - What is optimum temperature and optimum pH?
Ans: - Optimum temperature: -Every enzyme works at its maximum rate at a specific
temperature called as the optimum temperature.
Optimum pH: -All enzymes work at their maximum rate at a narrow range of pH,
called as the optimum pH.
9: - What is meant by “denaturation of enzymes”?
Ans: - When temperature is raised well above the optimum temperature, the heat energy
increases the vibrations of atoms of enzyme molecules and the globular structure of
enzyme is lost. This is known as denaturation of enzyme.
10: - What is saturation of active sites in enzymes?

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Ans: - When all the active sites of the enzymes are occupied, any more substrate molecules
don’t find free active sites. This state is called saturation of active sites.
11: - Explain Lock and Key model about mechanism of enzymes action.
Ans: - It was presented in 1894. According to it, both enzyme and the substrate possess
specific complementary geometric shapes that fit exactly into one another. This model
explains enzyme specificity.
12: - Explain the induced fit model of enzymes.
Ans: - It is more acceptable than “lock and key model”. In 1958, an American biologist Daniel
Koshland suggested a modification to the lock and key model and proposed the
induced-fit model. He said enzymes are flexible structures and their active site is
reshaped as the substrate interacts with the enzymes. According to this model the
active site is not a rigid structure rather it is molded into the precise position to
perform its function.
13: - What is meant by active energy?
Ans: - It is defined as minimum energy required starting a reaction.
14: - Write down two characteristics of enzymes.
Ans: - i. Almost all enzymes are proteins i.e. they are made of amino acids.
ii.Enzymes are usually specific for the type of reaction and for the nature of their
substrates.
15: - Describe the role of enzymes in food and paper industry.
Ans: - Food industry: -Enzymes that break starch into simple sugars are used in the
production of white bread, buns etc.
Paper industry: -Enzymes break starch to lower its viscosity that aids in making
paper.
16: - Differentiate b/w interacellular and extracellular enzymes.
Ans: - Intercellular enzymes work in the cytoplasm i.e. enzymes of glycolysis whereas
extracellular enzymes work in the stomach cavity i.e. pepsin enzymes.
17: - How value of pH affects the working of an enzyme? Give an example.
Ans: - A slight change in pH causes retardation in enzyme activity or blocks it completely.
Every enzyme has its specific optimum pH value. For example, pepsin is active in
acidic medium while trypsin shows its activity in alkaline medium. Change in pH can
affect the ionization of the amino acids at the active site.
18: - How reaction is influenced by substrate concentration? Explain.
Ans: - Increase in substrate concentration increase the rate of reaction. If enzyme
concentration is kept constant and amount of substrate is increased, a point is reached
where any further increase in substrate does not increase the rate of reaction any
more.
19: - What is biological detergent? Give an example also.
Ans: - Protease enzymes are used for the removal of protein stains from clothes. Amylase
enzymes are used in dish washing to remove resistant starch residues.
20: - Describe the use of enzymes in brewing industry.
Ans: - Enzymes break starch and proteins. The products are used by yeast for fermentation
to produce alcohol.

1: - What is meant by bio-energetics? Give an example.

Ans: - Bioenergetics is the study of energy relationships and energy transformations in living
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organism. Organisms obtain energy by metabolizing the food they eat or prepare.
Example: -Changing of potential energy stored in bodies into kinetic energy to for
the use of body.
2: - Define oxidation and reduction.
Ans: - For all life process, oxidation-reduction reactions are the direct source of energy.
Oxidation-reduction reactions involve exchange of electrons b/w atoms.
The loss of electron is called oxidation while the gain of electrons is called reduction.
3: - What is meant by ATP?
Ans: - The major energy currency of all cells is a nucleotide called adenosine triphosphate
(ATP). ATP is the main source for majority of the cellular functions like the synthesis
of macromolecules (DNA, RNA and proteins), movement, transmission of nerve
impulses, active transport, exocytose and endocytoses etc. ATP was discovered in
1929 by Karl Lohmann.
4: - Write down the sub units present in ATP.
Ans: - 1. Adenine-a double-ringed nitrogenous base.
2. A ribose-a five-carbon sugar
3. Three phosphate groups in a linear chain
5: - What are light and dark reactions?
Ans: - Light reactions: -During the first phase of photosynthesis, light energy is captured
and is used to make high-energy molecules. These reactions are known as light
reactions.
Dark reactions: -During the second phase of photosynthesis carbon dioxide is
reduced to make glucose, the energy in the form of ATP is utilized in this process and
is then stored in the bonds of glucose. Since these reactions don’t use light directly,
they are known as dark reactions.
6: - What is limiting factor in photosynthesis?
Ans: - Any environmental factor the absence or deficiency of which can decrease the rate of a
metabolic reaction, is called limiting factors.
7: - How temperature and light affect the intensity of photosynthesis?
Ans: - The increase in the intensity of temperature or light increase the rate of
photosynthesis whereas the decrease in intensity of temperature and light decrease
the rate of photosynthesis. But after the optimum temperature the more increase in
temperature slow down the photosynthesis process.
8: - Write down the function of stomata in the epidermis of leaf.
Ans: - The epidermis contains tiny pores known as stomata through which exchange of gases
b/w leaf cells and environment occur.
9: - What is meant by aerobic and anaerobic respiration?
Ans: - The cellular respiration occurring in the presence of Oxygen is called aerobic
respiration while the one that occurs in the absence of Oxygen is called anaerobic
respiration.
10: - What is alcoholic and lactic fermentation?
Ans: - Alcoholic Fermentation: -It occurs in bacteria, yeasts etc. In this type of anaerobic
respiration, pyruvic acid is further broken down into alcohol and CO2.
Lactic acid Fermentation: -It occurs in skeletal muscles of humans and other animals
rapidly as it is needed. This also happens in the bacteria present in milk. In this type of
anaerobic respiration, each pyruvic acid molecule is converted into lactic acid.
11: - What is glycolysis?
Ans: - A process in which glucose molecule is broken into two molecules of pyruvic acid is

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known as glycolysis. This is a type of anaerobic respiration.
12: - What is Krebs cycle?
Ans: - In Krebs cycle, the pyruric acid molecules are completely oxidized into CO2, and H2O.
Before entering in Krebs cycle, pyruric acid is changed into a 2-carbon compound
called acetyl-CoA. One molecule of CO2 and one NADH are also produced during this
reaction.
13: - What is electron transport chain?
Ans: - It is the last step of electron transport chain. In it NADH and FADH2 release electrons
and hydrogen ions. These electrons are taken up by a series of electron carriers. When
electrons move through the series of electron carriers they lose energy, which is used
to synthesize ATP molecules. At the end of the chain electrons and hydrogen ions
combine with molecular oxygen and form water.
14: - In what two forms energy exists in living organisms?
Ans: - In living organisms energy exists in two forms:
i. Kinetic energy: - This is actively involved in doing work.
ii. Potential energy: -This is stored for future use.
15: - Define photosynthesis with equation.
Ans: - Photosynthesis is the synthesis of glucose from carbon dioxide and water in the
presence of sunlight and chlorophyll, with oxygen and a by-product.
For equation See Text Book Page #120
16: - Write names of various photosynthetic pigments found in plants.
Ans: - Chlorophyll-a is the main photosynthetic pigment. Others are called accessory
pigments and include chlorophyll-b and carotenoids. Chlorophylls absorb mainly blue
and red lights. Some wavelengths not absorbed by chlorophyll-a are very effectively
absorbed by accessory pigments and vice-versa.
17: - What is the effect of carbon dioxide concentration on photosynthesis?
Ans: - As Carbon dioxide concentration rises, the rate of photosynthesis goes on increasing
until limited by other factor. Increase in carbon dioxide concentration beyond a
certain level causes the closure of stomata and it decreases the rate of photosynthesis.
18: - Describe the effect of intense light on the speed of photosynthesis.
Ans: - The rate of photosynthesis varies with light intensity. It decreases as light intensity
decreases and increases as intensity increases. However, at much higher light
intensity, the rate of photosynthesis becomes constant.
19: - What is the abbreviation of FAD?
Ans: - FAD(Flavin Adenine Dinucleotide is also a coenzyme like NAD+.
It gets 2 Hydrogen and reduces to FADH2.
20:- Write down the structure of Adenosene triphasphate?
Ans: - See Text book for structure.
21: - Explain that electron can be a source of flow of energy.
Ans: - See Text Book Page # 132.

1: - Define nutrition and nutrients.

Ans: - Nutrition: -The process in which food is obtained or prepared, absorbed and
converted into body substances for growth and energy, is called nutrition.
Nutrients: -Nutrients are the elements and compounds that an organism obtains and
use as energy source or as components for the synthesis of new material.

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2: - Define micro and macro nutrients.
Ans: - Macro nutrients: The elements which are required by plants in larger quantities are
called macronutrients. These are nine in number e.g. Carbon, Hydrogen, Oxygen,
Phosphorus, Potassium, Nitrogen, Sulphur, Calcium, Magnesium.
Micro nutrients: -The minerals elements which are required in lower quantities are
called micro nutrients. These are eight in number e.g. Iron, Molybdenum, Boron,
Copper, Manganese, Zinc, Chlorine, Nickel.
3: - Write down the purposes of nutrition.
Ans: - 1. It constitutes a source of energy for the organism.
2. It provides building material for growth and development.
3. It regulates various body functions.
4: - What is meant by minerals in food?
Ans: - Minerals: -Minerals are inorganic elements that originate in the Earth and can’t be
made in the body. They play important roles in various body functions and are
necessary to sustain life and maintain optimal health. It has two types.
1. Major minerals 2. Trace minerals.
5: - Define fertilizer and explain its types.
Ans: - Fertilizer: -As human cultivated plants it was learned that the addition of certain
materials to the soil sometimes resulted in plants with desirable characteristics. Such
materials were named as fertilizers. Fertilizers are broadly classified as organic or
inorganic.
i. Organic fertilizer: -An organic fertilizer is the one that is derived from either
plant or animal materials containing one or more essential elements.
ii. Inorganic fertilizer: -Inorganic fertilizers include rock phosphate, elemental
Sulphur, and gypsum that are not chemically modified. Most of them dissolve
readily in water and are immediately available to plants for uptake.
6: - What is eutrophication?
Ans: - It is the problem created in environment by the increase in chemical nutrients-
typically compounds containing nitrogen or phosphorous in an ecosystem.
7: - Write down the steps of nutrition in man.
Ans: - 1. Ingestion 2. Digestion 3. Absorption
4. Assimilation 5. Defecation
8: - Write down the major components of food.
Ans: - 1. Carbohydrates 2. Lipids 3. Proteins
4. Minerals in food 5. Vitamins
9: - Write down the function of Nitrogen and Magnesium.
Ans: - Nitrogen: -Plants get nitrogen in the form of nitrates. Nitrogen is a major component
of proteins, hormones, chlorophyll, vitamins and enzymes essential for plant life.
Nitrogen metabolism is a major factor in stem and leaf growth. Too much nitrogen can
delay flowering and fruiting. Deficiency of nitrogen can reduce yields, causes
yellowing of the leaves and stunt growth.
Magnesium: -Magnesium is a structural component of chlorophyll molecule and is

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necessary for functioning of plant enzymes to produce carbohydrates, sugar and fats.
It is used for fruit and nut formation and essential for germination of seeds. Deficiency
of magnesium causes yellowing and wilting of leaves.
10: - Name the major and trace minerals.
Ans: - Major minerals: -1. Sodium 2. Potassium 3. Chloride 4. Calcium 5. Magnesium
and Phosphorus. These are required in the amount of 100 mg or more per day.
Trace minerals: -1. Iron 2. Zinc 3. Copper 4. Chromium 5. Fluoride 6. Iodine
These are required in the amounts less than 100 mg per day.
11: - What is differentiation in cells?
Ans: - A process through which embryonic cells transform into mature cells with highly
specific function is called differentiation in cells.
12: - Name the disease caused by vitamin A.
Ans: - 1. Blindness 2. Colourblindness
13: - Write a brief note Vitamin C or Ascorbic acid.
Ans: - It participates in many reacations by donating electrons, essential to the activity of
many enzymes. Vitamin C is needed to form collagen that gives strength to connective
tissues. Its presence in the white blood cells enables the immune system to function
properly. Its deficiency causes connective tissue changes throughout the body. The
disease “Scurvy” results from lack of vitamin C.
14: - Write the symptoms of Scurvy disease.
Ans: - Symptoms of Scurvy include tiredness, nausea, muscle and joint pain, swollen
and bleeding gums, slow wounds healing and dry skin and hair.
15: - Write a brief note on vitamin D.
Ans: - The best-known function of vitamin D is to help regulate blood vessels of calcium and
phosphorus. Vitamin D increases absorption of these minerals from intestine and their
deposition in bones. Long term deficiency of vitamin D affects the bones. In children,
vitamin D deficiency leads to rickets, a condition in which bones weakens and bow
under pressure. In adults, its deficiency causes osteomalacia or soft bones.
16: - Write the role of water in body.
Ans: - Approximately 60% of the adult human body is composed of water. Nearly all of the
life sustaining chemical reactions require an aqueous environment. Water also
functions as the environment in which water-soluble foodstuff is absorbed in the
intestines and the waste products are eliminated in urine. Another essential role of
water is to maintain body temperature through evaporation.
17: - What are dietary fibers (Roughage)?
Ans: - Dietary fibers is the part of the human food that is indigestible. It is found only in plant
foods and it moves undigested through the stomach and small intestine and into the
colon.
18: - Write down the types of dietary fibers.
Ans: - 1. Insoluble fibres: -Insoluble fibers travel through the small intestine quickly. Wheat
bran, whole grain breads and cereals, as well as the skins of many fruits and
vegetables consist of insoluble fibres.
2. Soluble fibres: -These break down as it passes through the digestive tract, forming
a gel. This gel traps some substances and it helps in lowering the blood levels of
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cholesterol and sugars. Examples of soluble fibers are oats, beans, barely, and many
fruits and vegetables.
19: - What is meant by haemorrhoids?
Ans: - During constipation the swelling anal tissues is called haemorrhoids.
20: - Define balanced diet.
Ans: - A balanced diet may be defined as the one which contains the entire essential
nutrients in the correct proportion for the normal growth and development of body. It
is related to the state of one’s age, sex and activity.
21: - What is malnutrition? Explain the terms used in this.
Ans: - Problems related to nutrition are grouped as malnutrition. It weakens the immune
system, impairs physical and mental health, slows thinking stunts growth, and effect
fetal development, and leads to infectious disease. It is of two types.
1. Under nutrition: -This term is used for the condition caused by an improper or
insufficient diet. It most often refers to under resulting from inadequate
consumption, poor absorption, or excessive loss of nutrients.
2. Over nutrition: -It is used for the condition caused by over nutrition, resulting
from overeating or excessive intake of specific nutrients.
22: - Name the diseases caused by protein energy male nutrition
Ans: - 1. Kwashiorkor: -It is due to protein deficiency at the age of about 12 months when
breastfeeding is disconnected, but it can also develop at any time during a child’s
growing years. Children may grow to normal height but are abnormally thin.
3. Marasmus: -It usually develops between the ages of six months and one-year in
children. Patients lose all their body fat and muscle strength, and acquire a skeletal
appearance, Children with Marasmus show poor growth and look small for their
age.
23: - Name the diseases caused by the minerals.
Ans: - 1. Goiter: - Goiter is a condition caused by an insufficient amount of iodine in
the diet. Iodine is used by the thyroid gland to produce hormones that control the
body’s normal functioning and growth. If sufficient iodine is not available in a person’s
diet, the thyroid gland becomes enlarged and it results in swelling in the neck and the
condition is known as goiter.
2. Anemia: -Anemia is the most common of all mineral deficiency diseases. The term
anemia literally means “a lack of blood”. The condition is caused when the number of
red blood cells is reduced to a level lower than the normal. We know that hemoglobin
molecule contains a single atom of iron at its center. If the body fails to receive
sufficient amounts of iron, and adequate number of hemoglobin molecules will not be
formed. In that case, there are not enough functioning red blood cells.
24: - What is starvation?
Ans: - It is a severe reduction in nutrients and energy intake and is the most horrible
effect of malnutrition. In humans, prolonged starvation causes permanent organ
damage and eventually results in death.
25: - Obesity is known as the mother-diseases. Why?
Ans: - Obesity means becoming over-weight and it may also be due to malnutrition. People
who take food that contains energy more than their requirements and do very little
physical work can become obese. Obesity is called mother-diseases because it causes
many others diseases e.g. heart problem, hypertension and diabetes.
26: - What is famine?
Ans: - Famine is the lack of enough food to feed all the people living in an area. It is a
social and economic crisis that results in malnutrition and increased mortality.

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Historically, famines have occurred because of drought, crop failure, and because of
man-made causes such as war or misguided economic policies.
27: - What is Drought?
Ans: - A drought is a period of time when there is not enough water to support agriculture
and human needs. A drought is usually due to an extended period of below-normal
rainfall. Droughts decreases or even stop the crop yields resulting famine.
28: - What is mastication and lubrication?
Ans: - Mastication is the use of teeth to tear and crush food and the mixing of saliva with diet
is called lubrication.
29: - Define the following terms. OR Write down the steps of nutrition in man.
Ans: - Ingestion: -The process of taking in food.
Assimilation: -Conversion or incorporation of absorbed simple food into complex
substances constituting the body.
Defecation: -Elimination of undigested food from the body.
Digestion: -The process of breaking up complex substances into simpler substances.
Absorption: - Diffusion of digested food into blood and lymph.
30: - Write a brief note on man’s alimentary canal.
Ans: - The digestive system of human consists of a long tube that extends from the mouth to
the anus. This tube is called alimentary canal and its main sections are oral cavity,
pharynx, esophagus, stomach, small intestines, and large intestine. In addition, there
are many glands associated with the alimentary canal. These are the three pairs of
salivary glands, the pancreases and the liver.
31: - What is oral cavity?
Ans: - Oral cavity is the space behind mouth and has many important functions in the whole
process. Food selection is one of them. When food enters the oral cavity it is tasted and
felt. Its second function is the grinding of food by teeth. Its third and fourth function is
the lubrication and chemical digestion of food.
32: - Write down two functions of liver.
Ans: - i. Destroys the old red blood cells.
ii. Produce heat to maintain body temperature.
iii. Converts ammonia to a less toxic form i.e. urea.
iv. Removes amino groups from amino acids.
33: - What is meant by bolus?
Ans: - After the processes of chewing, lubrication and partial digestion the pieces of bread
and mutton are rolled up by the tongue into small, slippery, spherical mass called
bolus.
34: - What is meant by Peristalsis?
Ans: - Peristalsis means that the food moves from the oral cavity to the rectum. It is defined
as the rhythmic sequence of waves of contraction in the smooth muscles of the walls
of alimentary canal, thus squeezing the food down along the alimentary canal.
35: - What is meant by churning and chyme?
Ans: - Churning: -In the stomach, food is further broken apart through a process is called
churning.
Chyme: -The starch in our bite of bread and the protein in mutton have been partially
digested and the food has been converted to a soup-like mixture called chyme.
36: - What is meant by Villi?
Ans: - In small intestine, there are circular folds in the inner wall of the ileum. These folds
have numerous finger-like projections called villi (Singular Villus).

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37: - Name parts of large and small intestine.
Ans: - Large intestine: -1. Caecum 2. Colon 3. Rectum
Small intestine: -1. Duodenum (10 inch or 25 cm) 2. Jejunum (2.4 meter)
3. Ileum (3.5 meter)
38: - What is emulsification?
Ans: - Bile has bile salts which keep lipid droplets separate from one another, a process
called emulsification.
39: - What is meant by gall bladder?
Ans: - A pear shaped greenish yellow sac lies along the right lobe of liver on ventral side is
called gall bladder.
40: - What is meant by de-amination?
Ans: - The process of breaking amino acids by liver is called de-amination.
41: - Write a brief note on constipation
Ans: - Constipation is a condition where a person experience hard faces that are
difficult to eliminate. The main causes of constipation include excessive absorption of
water through colon, insufficient intake of dietary fibre, dehydration, use of medicines
and tumours in rectum or anus. Treatment of constipation is with a change in dietary
and exercise habit. The medicines called laxatives like paraffin are used for treatment.
42: - Define ulcer and write its symptoms.
Ans: - Ulcer is a sore in the inner wall of gut. In Ulcer, the acidic juice gradually breaks
down the tissue of the inner wall.
Symptoms: -Ulcer include abdominal burning after meals or at midnight. Severe
ulcer may cause abdominal pain, rush of saliva after an episode of regurgitation,
nausea, loss of appetite and weight loss.
43: - Write a brief note on appendix.
Ans: - A non-functional finger-like process called appendix arises from the blind end of
caecum. Inflammation of appendix due to infection causes severe pain. The infected
appendix must be removed surgically other wise it may burst and inflammation may
spread in abdomen.
44: - Define vitamins and name the fat soluble and water-soluble vitamins.
Ans: - Vitamins are the chemical compounds that are required in low amounts but are
essential for normal growth and metabolism. It has two major groups.
i.Fat-soluble: -The vitamins which are soluble in fat are called fat-soluble vitamins
like A, D, E and K.
ii. Water soluble: - The vitamins which are soluble in water are called water soluble
vitamins like B and C.
45: - Describe the role of Iron, Copper, Chlorine and Boron.
Ans: - Iron: - Necessary for photosynthesis, activates many enzymes.
Copper: - Component of several enzymes.
Chlorine: - Involved in osmosis of water.
Boron: - Important in sugar transport, cell division and synthesizing certain
enzymes.
46: - What is sphincter? Describe its types too.
Ans: - Sphincter are openings which are guarded by muscles. It has two types.
i. Cardiac sphincter: -It is located b/w stomach and oesophagus.
ii. Pyloric sphincter: -It is located b/w stomach and small intestine.
47: - What is meant by tetany?

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Ans: - Deficiency of Calcium causes spontaneous discharge of nerve impulses which may
result a disease, called tetany.
48: - Write the role of Phosphorus and Zinc in plants.
Ans: - Phosphorus: -Component of ATP, nucleic acids, and coenzymes, necessary for seed
germination, photosynthesis, protein formation etc.
Zinc: - Required in a large number of enzymes.
49: - Name of two juices excreted from small intestine.
Ans: - i. Pancreatic Juice ii. Intestinal juice
50: - Write the role of dietary fiber (Roughage) in man’s diet.
Ans: - Fibre (Roughage) prevents and relieves constipation by stimulating the concentration
of intestinal muscles. Soluble fibre helps in lowering blood cholesterol and sugar level.
Insoluble fibre speeds up the movement of carcinogens from intestine.
51: - What is meant by protein?
Ans: - Proteins are composed of amino acids. Proteins are essential components of the
cytoplasm, membranes and organelles. They are also the major components of
muscles, ligaments, and tendons.
52: - Name the parts of large intestine.
Ans: - i. Caecu ii. Colon iii. Rectum
53: - What is the effect of pepsinogen on HCl(Hydrochloric acid)?
Ans: - HCl converts the inactive enzyme pepsinogen into its active form i.e. pepsin. HCl
also kills microorganisms present in food‫۔‬

1: - Write a brief note on Xylem and Phloem tissue.

Ans: - Xylem tissue: -Xylem tissue is responsible for the transport of water and
dissolved substances from roots to aerial parts. It consists of vessel elements and
tracheids.
Phloem tissue: -Phloem tissue is responsible for the conduction of dissolved organic
matter (food) between different parts of plant body. It consists of sieve tube cells and
companion cells.
2: - What is meant by apoplast and symplast pathway in root.
Ans: - Apoplast pathway: - When water travels along cell walls and through intercellular
spaces to reach the core of the root then we call this pathway as apoplast pathway.
Symplast pathway: -The rest of the plant living (other than apoplast) is termed as
symplast pathway. In the symplast pathway, water moves through plasmodesmata.
3: - What is meant by transpiration? Also write its types.
Ans: - The loss of water by evaporation from a plant surface is called transpiration. It is of
three types.
I. Stomatal transpiration
II. Cuticular transpiration
III. Lenticular transpiration
4: - Name the factors affecting on transpiration.
Ans: - i. Temperature ii. Surface area of leaf
iii. External Humidity iv. Atmospheric pressure
5: - Define desiccation and transpiration pull.
Ans: - Desiccation: -During the conditions of drought, loss of water from plant results in
serious problem called desiccation. It wilts and often dies.

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Transpiration pull: -Transpiration creates pulling force called transpirational pull
which is principally responsible for the conduction of water and salts from roots to the
aerial parts of plant body.
6: - What do you know about tension theory?
Ans: - The process by which water is raised to considerable heights in plants has been
named cohesion tension theory. According to this theory, the force which carries
water upward through the xylem is transpirational pull. Transpiration creates a
pressure difference that pulls water and salts up from the roots.
7: - What are adhesion and cohesion?
Ans: - Adhesion: -Water molecules adhere to the walls of xylem tube, it is called adhesion
between water and tube.
Cohesion: -Water molecules cohere to each other, this phenomenon is called cohesion.
8: - What is meant by flow-mechanism?
Ans: - In flow-mechanism, food is moved from source to sinks.
Source: -Include the exporting organs, typically a mature leaf of storage organ.
Sinks: -Sinks are the areas of active metabolism or storage e.g. roots, tubers,
developing fruits and leaves.
9: - Write about transport in man.
Ans: - In man transport is carried out by two complicates methods.
i. Blood circulatory system. ii. Lymphatic system
10: - What is closed blood circulatory system?
Ans: -In this system the blood confines to the blood vessels e.g. arteries, veins and
capillaries during its circulation. It is more elaborated, complicated ad efficient
system.
11: - Write a brief note blood.
Ans: - Blood is a specialized body fluid that is composed of a liquid called blood plasma and
blood cells. The weight of blood in our body is about 1/12th of our body. The average
adult body has about 5 liters of blood. In a healthy person, plasma constitutes about
55% by volume of blood, and cells or cell-like bodies are about 45% by volume of the
blood.
12: - What is blood plasma?
Ans: - Plasma is primarily water in which proteins, salts, metabolites and wastes are
dissolved. Water constitutes about 90-92% of plasma and 8-10% dissolved
substances.
13: - Write down the function of fibrinogen and albumin.
Ans: - Fibrinogen: -It helps to clot the blood.
Albumin: -It helps to maintain the water balance of blood.
14: - Name the cells present in blood.
Ans: - i. Red blood cells (Erythrocytes)
ii. White blood cells (Leukocytes)
iii. Platelets (Thrombocytes)
15: - Explain the types of white blood cells.
Ans: - There are about five different types of white blood cells, which are divided into 2
categories on the basis of granules.
1. Granulocytes: -Granulocytes have granules cytoplasm.
i. Neutrophils: -They destroy small particles by phagocytosis.
ii. Eosinophils: -They break inflammatory substances and kill parasites.
iii. Basophils: -They prevent blood clotting by releasing an anticoagulant.

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2.Agranulocytes: -They have clear cytoplasm (no granules).
These types are as follows.
i. Monocytes: -They produce macrophages and engulf the germs and the dead
cells.
ii. B & T Lymphocytes: -They produce antigens and kill germs.
16: - Write brief note red blood cells.
Ans: - These are the most numerous of blood cells. A cubic millimeter of blood contains 5 to
5.5 million of RBCs in males, and 4 to 5 million in females. About 95% of the cytoplasm
of RBCs is filled with hemoglobin, which transports O2 and small amounts of CO2. The
remaining 5% consists of enzymes, salts and other proteins. These are biconcave and
have an elastic cell membrane. Average life span of RBC is about four months (120
days) after which it breaks down in liver and spleen by phagocytosis.
17: - Write down the immediate and permanent treatment of Myocardial
Infarction.
Ans: - Immediate treatment: -Immediate treatment for suspected acute myocardial
infarction includes oxygen supply, aspirin, and sublingual tablet of glycerol trinitrate.
Permanent treatment: -Its permanent treatment is by angioplasty which means
mechanical widening of a narrowed or totally obstructed blood vessels or bypass
surgery which means surgery in which arteries of veins from elsewhere in the
patient’s body are grafted to the coronary arteries to improve blood supply to heart
muscles.
18: - Write down the importance of transpiration.
Ans: - Transpiration plays an important role in the life of plants as it provides the forces or
tension to pull water and mineral ions up the xylem vessels from the roots to the
leaves. This is especially important in warmer environments. Moreover, the wet
surfaces of leaf cells allow gaseous
exchange.
19: - Transpiration is called necessary evil. Why?
Ans: - Transpiration is called necessary evil. It means that transpiration is a potentially
harmful process but is unavoidable too.
20: - What is meant by heart beat?
Ans: - The alternating relaxations and contractions make up the cardiac cycle and one
complete cardiac cycle makes one heartbeat.
21: - Write down the functions of roots.
Ans: - In addition to anchor the plant, roots perform two other vital functions. First; they
absorb water and salts from soil. Second; they provide conducting tissues distributing
these substances to the tissues of stem.
22: - How diffusion is different from transport?
Ans: - One method for the movement of molecules is diffusion but it alone can’t fulfill the
needs. It takes much time for materials in solution to diffuse even a few inches. For the
transport of materials, diffusion can work only in unicellular and simple multicellular
organisms, because every corner for their body is in close and direct contact with
environment. In complex multicellular bodies, cells are far apart from environment
and such bodies need a comprehensive system for the transport of materials.
23: - Define myocardial infarction and write down its symptoms.
Ans: - The term myocardial infarction is derived from myocardium (the heart muscle)
and infarction (tissue death). It is more commonly knows as a heart attack.
Symptoms: -Severe chest pain is the most common symptom of myocardial

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infarction and may be in the form of sensation of tightness, pressure, or squeezing.
Pain radiates most often to left arm, but may also radiate to lower jaw, neck, right arm
and back. Loss of consciousness and even sudden death can occur in myocardial
infarction.
24: - How can blood plasma be separated from blood?
Ans: - Blood is taken from an artery and an anticoagulant is mixed in it. After about 5
minutes, plasma separates from blood cells, which settle down.
25: Write brief note platelets.
Ans: - They are not cells, but are fragments of large cells of bone marrow, called
megakaryocytes. They don’t have any nucleus and any pigment. One cubic millimeter
of blood contains 250,000 platelets. The average life span of blood platelets is about 7
to 8 days. Platelets help in blood clotting. The clot serves as a temporary seal at the
damaged area.
26: - Write about the diseases of blood.
Ans: -i. Leukaemia (blood cancer): -It is the production of great number of immature and
abnormal white blood cells. This is caused by cancerous mutation in bone marrow or
lymph tissue cells. The mutation results in uncontrolled production of defective white
blood cells.
ii. Thalassaemia: -It is also called Cooley’s anemia on the name of Thomas Cooley, an
American physician. It is a genetic problem due to mutations in the gene of
hemoglobin. The mutation results in the production of defective hemoglobin and the
patient can’t transport oxygen properly. It can be cured by bone marrow transplant
but it does not give 100% cure rate.
27: - What is meant by universal donors and universal recipients?
Ans: - Universal donors: -O blood group individuals are called universal donors because
they can donate blood to the recipients of every other blood group.
Universal Recipients: -AB blood group individuals are called universal recipients
because they can receive transfusions from the donors of every other blood group.
28: - What is meant by agglutination?
Ans: - If the transfusion is occurred between two different blood group then the antibodies
present in the plasma of recipients make clump around the antigens present in the
plasma of donors, this clumping of cells is called agglutination.
29: - Write about the chambers of heart.
Ans: - Human heart consists of four chambers, like the heart of birds and mammals. The
upper thin-walled chambers are called left and right atria (single atrium), and the
lower thick-walled chambers are called left and right ventricles. Left ventricle is the
largest and strongest chamber in heart.
30: - Write briefly on human heart.
Ans: - Heart is a muscular organ responsible for pumping blood through blood vessels by
repeated contractions. The term “cardiac” means related to the heart. The bulk of the
walls of heart chambers is made of cardiac muscles. In human, heart is situated
between lungs, in the middle of chest cavity (thorax) under breastbone. Heart is
enclosed in a sac known as pericardium. There is a fluid, known as pericardial fluid,
between pericardium and heart walls. It reduces friction between pericardium and
heart, during heart contractions.
31: - What is meant by the double pump of heart?

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Ans: - Human heart works as a double pump. It receives deoxygenated (with less oxygen)
blood from body and pumps it to lungs. At the same time, it receives oxygenated (with
more oxygen) blood from lungs and pumps it to all body. Inside heart chambers, the
deoxygenated and oxygenated bloods are kept separated.
32: - What is pulmonary circulation?
Ans: - The pathway on which deoxygenated blood is carried from heart to lungs and in
return oxygenated blood is carried from lungs to heart is called pulmonary circulation.
33: - What is systemic circulation or circuit.
Ans: -The pathway on which oxygenated blood is carried from heart to body tissues and in
return deoxygenated blood is carried from body tissues to heart is called systemic
circulation or circuit.
34: - Define bicuspid and tricuspid valve.
Ans: - Tricuspid Valve: -The opening between right atrium and right ventricle is guarded by
a valve known as tricuspid valve because it has three flaps.
Bicuspid Valve: -The opening between left atrium and left ventricle is guarded by a
valve known is bicuspid valve because it has two flaps.
35: - What is meant by cardiac diastole, atrial systole and ventricular systole?
Ans: - Cardiac diastole: -Atria and ventricles relax and blood is filled in atria. This period is
called cardiac diastole.
Atrial systole: -When the filling of blood in atria completes, both atria contract and
pump blood towards ventricles. This period in cardiac cycle is called atrial systole.
Ventricle systole: -When both ventricles contract and pump blood towards body and
lungs. The period of ventricular contraction is called ventricular systole.
36: - What is meant by “lubb” dubb” sounds in heart?
Ans: - When ventricles contract tricuspid and bicuspid valves close and “lubb” sound is
produced. Similarly, when ventricles relax, the semi lunar valves close and “dubb”
sound produced. “Lubb-dubb can be heard with the help of stethoscope.
37: - Name the blood vessels.
Ans: - i. Arterie s ii. Capillaries iii. Veins
38: - Write briefly about arteries.
Ans: - Arteries are the blood vessels that carry blood away from heart. The structure of
arteries is well adapted to their function. The walls of an artery are composed of three
layers. The outermost layer is made of connective tissues. The middle one is made up
of smooth muscles and elastic tissue while innermost layer is made up of endothelial
cells.
Lumen: -The hollow internal cavity in which blood flows is called lumen.
Arterioles: -When arteries enter body organs, they divide into smaller vessels known
as arterioles.
39: - Write a brief note on capillaries and veins.
Ans: - Capillaries: -These are the smallest blood vessels present in tissues. These are
formed by the divisions of arterioles. The exchange of materials between blood and
tissues fluid is carried out through capillaries. These walls are composed of only a
single layer of cell i.e. endothelium.
Veins: -A vein is a blood vessel that carries blood towards heart. These are well-
adapted to their functions. The walls of an artery are composed of three layers. The
outermost layer is made of connective tissues. The middle one is made up of smooth
muscles and elastic tissue while innermost layer is made up of endothelial cells. But

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the middle layer of vein is comparatively thin. The lumen of the veins is broader than
that of arteries.
40: - What are venules?
Ans: - In a tissue, capillaries join to form small venules, which join to form veins. Most veins
have flaps called valves that prevent the backflow of blood.
41: - What is aortic arch and dorsal aorta?
Ans: - Aortic arch: -The oxygenated blood leaving left ventricle of heart is carried in a large
artery which ascends and forms an aortic arch. The arch curves left and descends
inferiorly into body.
Dorsal aorta: -From the upper surface of aortic arch, three arteries emerge, which
supply blood to head, shoulders and arms. As aorta passes down through thorax, it
becomes dorsal aorta. It gives off many branches.
42: - What are cardiovascular diseases? Write their types too.
Ans: - The diseases that involve the heart of blood vessels are collectively called
cardiovascular disorders. These diseases have similar causes, mechanism and
treatment. Its types are as follow.
i. Atherosclerosis and Arteriosclerosis ii. Myocardial infarction
43: - What are aethroscloras and arteroscloras?
Ans: - Atherosclerosis and arteriosclerosis are the diseases of arteries. These diseases also
lead to heart diseases. Atherosclerosis is commonly referred to as ‘narrowing” of
arteries. It is a chronic disease in which there is accumulation of fatty materials,
cholesterol of fibrin in arteries. When this condition is severe, arteries can no longer
expand and contract properly, and blood moves through them with difficulty.
44: - What is meant by plaques and Thrombus and Embolus?
Ans: - Plaques: -Accumulation of cholesterol is the prime contributor to arthrosclerosis,
which results formation of multiple deposits called plaques.
Thrombus: -Plaques can form blood clots called thrombus within arteries.
Embolus: -if a thrombus dislodges and becomes free-floating, it is called an embolus.
45: - What is pus and how it is prepared?
Ans: - WBCs die in the process of killing the germs. These dead cells accumulate and make
the white substance called pus, seen at infection sites.
46: - What is cardiac cycle?
Ans: - The alternating contraction and relaxation of the heart chambers is called the cardiac
cycle.
47: - Differentiate b/w stomata and lenticels.
Ans: - Stoma: -The leaves and young stems have stomata (singular stoma) in their
epidermis. The gaseous exchange occurs through these stomata.
Lenticels: -There are certain pores in the layer of bark. These are called lenticels. The
lenticels allow air to pass through them.
48: - Differentiate b/w systole and dia-systole.
Ans: - The period of ventricular contraction is called systole and their relaxation is called
diastole.
49: - What is vascular surgery?
Ans: -Vascular surgery is a field in surgery in which diseases of arteries and veins are
managed by surgical methods. A vascular surgeon treats the diseases of all parts
of blood circulatory system except that of heart and brain.
50: - What is angina pectoris?

Prepared and composed by Amir Public School & Science Academy 11-D Shaheenabad
Amir Public School (31) Biology 9th
& Science Academy Session: 2021-22
WARNING: - Amir Public School and Science Academy reserves the right
pursue Legal action against anyone who will violate the copy rights.
Ans: - Angina pectoris means “chest pain”. It is not as severe as heart attack. The pain may
occur in heart and often in left arm and shoulder. It is a warning sign that blood supply
to heart muscles is not sufficient but shortage is not enough to cause tissue death.
51: - What is meant by embolus?
Ans: - Plaques can form blood clots called thrombus within arteries. If a thrombus
dislodges and becomes free-floating, it is called embolus.
52: - What is meant by stomatal transpiration and transpirational pull?
Ans: - Stomatal transpiration: -Transpiration which occurs through stomata is
called stomatal transpiration.
Transpirational Pull: -Transpiration creates a pulling force called transpirational pull
which is principally responsible for the conduction of water and salts from roots to the
aerial parts of plant body.
53: - What is blood group system?
Ans: - Blood group systems are a classification of blood based on the presence of absence of
antigens on the surface of red blood cells.
54: - Write down the symptoms of Dengue fever.
Ans: - See Text book.

Prepared and composed by Amir Public School & Science Academy 11-D Shaheenabad