Classification CHAPTER 1
Movement: This is organisms moving themselves or moving parts of themselves into
new areas or to change position.
Respiration: Chemical reaction in all cells that releases energy by breaking down
nutrients (glucose) either in presence or absence of oxygen.
- Living organisms use this energy for movement, growth, repair
and reproduction
Sensitivity: This is the organism's ability to respond or detect stimuli in the internal or
external environment and to make appropriate responses
Growth: This is the permanent increase in size and dry mass by an increase in cell
number or size
o It also always involves making more complex chemicals like proteins and this is
why their dry mass increases.
Reproduction: Process that makes more of the same kind of organism.
Excretion: Removal of waste products from metabolism, toxic materials and substances
in excess requirements.
- E.G: CO2 and Urea
- Anabolism: Build up large molecule from small one
- Catabolism: Brake down to small molecule from large one
Nutrition: Taking in of materials for energy, growth and development
Types of Nutrition:
Atrophic:
The organism can make its own organic food from simple inorganic molecules by using light or
chemical energy like photosynthesis
Heterotrophic:
Organisms that feed on a ready-made organic food
Types of Heterotrophs:
Holozoic: Ingests and digests its food inside the body
Saprozoic: Feeds on dead remains and digests the food outside the body
Parasitic: An organism which derives its food from another organism (Host),
whilst the host is still alive (Flea is an example)
Types of Holozoic
Herbivores: Feed on a plant material only
Carnivores: Feed on animal material only
Omnivores: Feed on both plant and animal materials
Concepts and use of the classification system:
Organisms can be classified into groups by the features that they share
Classification systems aim to reflect evolutionary relationships and allow us to study
them easily
The sequences of bases in DNA and of amino acids in protein are used as more accurate
means classification
Organisms which share a more recent ancestor (are more closely related) have base
sequences in DNA that are more similar than those that share only a distant ancestor
Classification of living organisms:
The living organisms are classified into 5 large group Kingdoms, according to the common
features present between the members of the same groups
Living organisms consist of
Kingdom: Animalia
Characteristics:
Multicellular, Cells have a nucleus but no cell walls, feed on organic substances
made by other living organisms. Most can move actively, hunting for food
Kingdom: Plantae
Characteristics: Multicellular, have a nucleus, cell walls made of cellulose and
often contain chloroplasts. They are autotrophs as they food by photosynthesis.
Some may have roots, stems and leaves
Kingdom: Fungi
Characteristics: Usually multicellular, have nuclei, have cell walls made of chitin
and are saprophytic.
Kingdom: Protoctista
Characteristics: Multicellular or unicellular, cells have a nucleus and may or may
not have chloroplasts, some feed by photosynthesis and others feed on organic
substances made by other organisms.
Kingdom: Prokaryote
Characteristics: Unicellular organisms, no nucleus, have cell walls made of
peptidoglycan or murine. Don’t have mitochondria.
The Classification system
Kingdom -> Phylum -> Class -> Order -> Family -> Genus -> Species
Species: Group of living organisms that share common features and have the ability to
interbreed and produce fertile offspring
Why do we classify organisms?
To ease the study of living organisms
There are other classification as:
DNA: It Is the most accurate and looks at base sequences in the DNA of other organisms
Anatomy: Internal body structure (dissection)
Morphology: External shape or appearance
Using Amino acids sequences
Describe how can we use DNA in classification or Suggest how study of the DNA of (Animal)
helps to classify them?
We observe DNA base sequences. If sequences are similar it indicates that the
organisms are closely related species that share a more recent common ancestor. If not
then it tells us that they are different species
The Binomial system for naming species
It is an internationally agreed system in which the scientific name of an organism is
made up of 2 parts showing the genus and species
Helps prevent confusion between others of different languages
First name : Genus with upper case
2nd Name: species with lower case
Example: Humans are known as Homo sapiens or H.sapiens
Closely related organisms probably came from a common ancestor species, in the past.
By looking at features of fossils (or fossil DNA or proteins) we can draw CLADOGRAMS
KING PHILIP CAME OVER FROM GREAT SPAIN
FUNCTION OF DNA IN CELLS:
Stores genetic information and can be copied to pass on information to new cells. Also holds
the codes for specific proteins
Vertebrates
Fish Amphibians Reptiles Birds
Body cover Scaley, moist Moist, smooth non Dry scaly skin to Feathers on the
streamlined cover scaley skin prevent water loss body and scales on
legs
Limbs No proper ones but have Youngs have fins and 4 short limbs or 2 legs and wings
fins used in swimming adults have 4 legs limbless
and balance
Ears No ears but have lateral External ears on skin Internal ear drum with Holes that lead to
lines to detect vibrations surface occasional external ear drums
in water
Eggs Lay eggs in water, Same as Fish Lay leathery eggs with Lay eggs with hard
covered in jelly spongy water proof shells
shells to prevent
drying out
Habitat Aquatic Double life (Aquatic and Land Land
land)
Fertilization External External Internal Internal
Development External External External External
Control of Ectothermic Ectothermic Ectothermic Endothermic
Body Temp
Breathing Boney gill slits or Gas exchange through Lungs Lungs
operculum thin skin and simple
lungs
Extra 3rd eye lid to protect Beaks with diff
eyes from sandy shapes depending
storms on food they eat
Describe how nocturnal animals are adapted to the night:
They have good sense of hearing / smell /sight to make it easier to navigate throughout the
night. They also have a lot of Rod cells in their eyes that allow them to see better in the night.
They also hide and refuge in the morning.
Mammals
Body cover Hair/ Fur/ Whiskers
Limbs Have 4 legs or wings or fins OR 2 legs and 2 arms
Ears External ears
Eggs Don’t lay eggs but give birth
Habitat Land and some times water
Fertilization Internal
Development Internal
Control of Body Temp Endothermic
Breathing Lungs
Extra The females have mammary glands for suckling youngs.
They have different kinds of teeth depending on their diet
Invertebrates (ARTHROPODS)
Feature Myriapods Crustaceans Insects Arachnids
Number of pairs 1 or 2 pairs per body More than 5-10 3 pairs 4 pairs
of legs segment
Body regions Head and a body which is Head cephalothorax Head, Thorax and Head-
not divided into thorax and and abdomen abdomen cephalothorax
abdomen And abdomen
Number of pairs 1 pair 2 pairs 1 or 2 pairs Absent
of antennae
Type of eyes Simple Compound Compound, some Many pairs of
may have simple simple
Wings Absent Absent May have 1 or 2 Absent
pairs
Compound eyes: Detect quick movement
Simple eyes: Detect light and dark only
Antennae: Sensitive organs that sense chemicals and touch
Arachnids may have pedipalp for food collection and a chelicera for defense (contains
poison gland)
Some of them have claws, hooks and pincers to catch preys
What do all invertebrates share?
Arthropod legs
Arthropod muscle connection
INSECTS
ARACHNIDS
CRUSTACEANS
MYRIAPODS
CLASSIFICATION OF PLANTS
Ones you need to know: Flowering plants and Non flowering plants (FERNS)
Flowering plants: They are a group of plants which have flowers. Inside the flowers the seeds
develop
We split them into 2 parts: Monocotyledons and Dicotyledons (Mono = 1) (Di= 2) (Cot = seed)
Point of Comparison MONOCOTYLEDONS DICOTLYLEDONS
Roots Fibrous roots Tap root
Seeds Have 1 cotyledon (seed) Have two cotyledons
Leaves Have no stalk / petioles Have stalk and petioles
Flower parts Flower parts (sepals and petals) come The flower parts are in
in 3s groups of 4-5
Width Narrow leaves Broad leaves
Veins Parallel veins Branched veins
Their seeds
Monocotyledons:
Dicotyledons:
Their seed leaves
Monocotyledons: Dicotyledons:
Their LEAF VEINS:
MONO: DI:
Their roots:
Mono: Di:
FIBROUS ROOTS Looong Tap root
Their Petals:
EXTRA ------ Their stems:
Monocot
Dicot
Features of FERNS
They reproduce using spores produced under their fronds (leaves)
They develop an underground stem (rhizome)
They use roots for anchorage in soil and absorbing nutrients
After winter, new fronds unroll from “fiddlehead” structures
FUNGI KINDGODM:
Unicellular: Yeast
Multicellular: Bread mould fungus
Useful fungus: Mushroom (Food), yeast (Making bread and alcohol), Penicillium (Antibiotic)
Harmful fungus: Athlete’s feet and Ringworm
Characteristics of cell : Nucleas/ Cell wall (Chitin)/ No chloroplasts/ No photosynthesis
SPROANGIUM DRAWING
Sporangium SPORES
Arial Hyphae Body of fungus: Mycelium
Fine threds: Hyphae
Rhizoid hyphae
How does a fungus reproduce?
Asexual reproduction through mitosis produces spores in the sporangium. The
sporangium eventually bursts and releases spores which are then carried by wind until
falling into suitable medium that allows them to germinate into a new fungus.
How do they feed / obtain nutrient / get their food / absorb their food ?
They are saprophytic and they do extracellular digestion. The fungus hyphae secretes
enzymes out onto the food. These amylase and protases enzymes then break down the
food into small soluble nutrients (glucose and amino acid). The fungus feeding hyphae
absorbs the nutrients by diffusion or active transport.
Compare between fungus and plant
Both have cell walls and but their cell wall are made of different materials (Fungus is chitin and plant is
cellulose). Also, the fungus doesn’t have chloroplasts but plants do.
Compare between fungus and animal
Both are heterotrophs. They also both store excess glucose in the form of glycogen granules. However, the
fungus has a cell wall but animals don’t have a cell wall.
Protoctista
Unicellular organisms that inhibit both animal cell structures and plant structures
Cell structure: Cell membrane/ Cytoplasm/ Nucleus/ Chloroplasts
Examples:
Paramecium (LIKE ANIMALS): Chlamydomonas (LIKE PLANT):
Prokaryotes Shapes: Spiral, Rod, Coccus.
/ Bacteria: ALL UNICELLULAR
Characteristics in all of them:
No nucleus / No membrane bound organelles (i.e. no mitochondria) / Cell wall made of
peptidoglycan or murein / Loop of circular DNA or nucleoid / Plasmid (Circular DNA) / Small
ribosome 70 – s / cell membrane / cytoplasm.
SOME Characteristics:
Flagellum for movement
Capsule for protection
Pilli
Types of bacteria:
Uses:
Yoghurt/ Cheese/ Sewage treatment/ Biotechnology / Genetic engineering
Harmful
Cholera / Syphilis / Gonorrhea / Typhoid
Feeding : They are saprophytic and they decompose or decay dead bodies.
Reproduction: Asexual reproduction through a type of mitosis called binary fission where the DNA
duplicates and the bacteria divides into 2
Viruses
They are organisms that can be non-living or living depending on where they are. Viruses can
do all life processes except for reproduction. They must be withing a host to reproduce.
They are very harmful organisms as they can cause:
AIDS
Small pox
Common cold
Influenzas
Polio
Ebola
Hepatitis C
