Worksheet-6

BIOLOGY Practice Book

Worksheet-6 Q.7 The exchange of material between the

nucleus and the cytoplasm is carried out
(The Cell)
through:
Q.1 Nucleus may be ______ or _____ in shape. A) Endoplasmic reticulum
A) Irregular, spherical B) Nuclear pores
B) Rectangular, spherical C) Vacuoles
C) Elongated, spherical D) Nuclear envelope
D) Ellipsoidal, square Q.8 The number of nuclear pores in the
Q.2 The example of polynucleate cells is: nuclei of differentiated cells such as
A) Smooth muscle cells erythrocytes is only:
B) Striated muscle cells A) 1-2 nuclear pores/nucleus
B) 2-3 nuclear pores/nucleus
C) Striped muscle cells
C) 3-4 nuclear pores/nucleus
D) Skeletal muscle cells
D) 5-6 nuclear pores/nucleus
Q.3 In non-dividing phase nucleus contains
_______ and soluble sap called _____ Q.9 The example of undiffentiated cells is
respectively. that of:
A) Chromatin network, nucleoplasm A) Leucocytes C) Osteocytes
B) Erythrocytes D) Egg cells
B) Chromosomes, nucleoplasm
Q.10 Number of nucleoli may be:
C) Nucleoplasm, chromatin network
A) Many per nucleus
D) Chromatin network, cytoplasm
B) One per nucleus
Q.4 The hereditary material is in the form
of chromosomes, which control: C) One or more per nucleus
D) Zero per nucleus
A) Reproductive activities of the cell
Q.11 It is the _______ where ribosomes are
B) Somatic activities of the cell
assembled and then exported to the
C) All activities of the cell cytoplasm via nuclear pores.
D) Physiological activities of the cell A) Nucleus
Q.5 The membrane that separates the B) Nucleoplasm
nuclear material from the cytoplasm is: C) Nuclear envelope
A) Plasmalemma D) Nucleolus
B) Cytoplasmic membrane Q.12 During cell division thread like
C) Plasma membrane material is converted into darkly
D) Nuclear membrane stained structures known as:
Q.6 The outer and inner nuclear membranes A) Nucleoli C) Nucleosomes
are continuous at certain points, B) Nuclear membrane D) Chromosomes
resulting in the formation of: Q.13 The place on chromosomes where
A) Endoplasmic reticulum spindle fibres are attached during cell
division is called:
B) Nucleolus
A) Centromere
C) Nuclear pores
B) Chromatid
D) Chromosomes

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C) Secondary construction A) 23 chromosomes C) 4 chromosomes

D) Nucleosome B) 46 chromosomes D) 13 chromosomes
Q.14 Each chromosome consists of ________ Q.22 Number of chromosomes in pollens of
at the beginning of cell division. onion is:
A) Two non-sister centromeres A) 14 C) 08
B) Two sister chromatids B) 16 D) 07
C) Two non-sister chromatids Q.23 Number chromosomes in the sperms of
frog is:
D) Two sister centromeres A) 26 C) 14
Q.15 All the information needed to control B) 13 D) 16
the activities of the cell is located on the
Q.24 The network of channels which is often
chromosomes in the form of:
continuous with plasma membrane and
A) Centromeres C) Genes also appears to be in contact with the
B) Kinetochores D) Genetic material nuclear membrane is called as:
A) Endoplasmic reticulum
Q.16 The number of chromosomes in
_______ remains constant generation B) Chromatin network
after generation. C) Reticular formation
A) All individuals of same species D) Microtubular network
B) All individuals of different species Q.25 Like intermediate filaments ________
also provides mechanical support to the
C) Few individuals of same species cell so that its shape is maintained:
D) Few individuals of different species A) Microfilaments
Q.17 In man each cell contains: B) Microtubules
A) 23 chromosomes C) 8 chromosomes C) Golgi apparatus
B) 46 chromosomes D) 48 chromosomes D) Endoplasmic reticulum
Q.26 Two morphological forms of endoplasmic
Q.18 Number of chromosomes in each cell of
reticulum are:
fruit fly, Drosophila melanogaster is:
A) ER with the ribosome and ER without
A) 46 C) 48 ribosome
B) 26 D) 8 B) ER with cisternae and ER without
Q.19 In each cell of Garden pea, the number cisternae
of chromosomes is: C) ER with enzymes and ER without
enzymes
A) 26 C) 08
D) Rough endoplasmic reticulum and
B) 16 D) 14 sarcoplasmic reticulum
Q.20 The number chromosomes in germ cells is: Q.27 The apparatus, which was found
A) Tetraploid C) Haploid virtually in all eukaryotic cells and
consists of stacks of flattened membrane
B) Triploid D) Diploid bound sacs is called as:
Q.21 Human sperms and eggs have: A) Golgi Apparatus

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B) Granum B) Stellate, rods or filamentous

C) Endoplasmic reticulum C) Vesicles, star like or filamentous
D) Intergranum D) Round, rods or triangular
Q.28 Inner concave surface of Golgi apparatus Q.34 The number, shape and internal
is: structure of mitochondria:
A) Maturation face C) Forming face A) Vary rarely C) Vary widely
B) Cis face D) Proximal face B) Do not vary D) Do not resemble
Q.29 The direction of flow of protein Q.35 The inner membrane of mitochondrion
products synthesized on ribosomes is as forms infoldings into the inner chamber
under: called:
A) Ribosomes  RER  Transport A) Mitochondrial cristae
Vesicles of ER  Golgi apparatus  B) Mitochondrial matrix
Golgi vesicles  Plasma membrane
C) Mitochondrial stroma
B) Ribosomes  SER  Transport
D) Mitochondrial sap
vesicles of ER  Golgi apparatus 
Golgi vesicles  Plasma membrane Q.36 The inner surface of cristae in the
mitochondrial matrix has small knob
C) Ribosomes  RER  Golgi vesicles like structures known as:
 Golgi apparatus  Plasma
membrane A) F1 particles C) Matrix

D) Ribosomes  RER  Golgi B) F0 particles D) F-ATPase

apparatus  Golgi vesicles  Plasma Q.37 Mitochondrial matrix contains in it a
membrane large number of:
Q.30 Blebs from tips of SER fuse with Golgi A) Enzymes and coenzymes
apparatus cisternae at:
B) Organic and inorganic salts
A) Forming face C) Trans face
C) Enzymes, coenzymes, organic and
B) Inner face D) Distal face inorganic salts
Q.31 In mammals, the pancreas secretes D) Enzymes, coenzymes, organic and
granules containing enzymes. Such inorganic salts and DNA with
granules are formed by: ribosomes
A) SER C) Golgi apparatus Q.38 Mitochondria extract energy from
B) RER D) Lysosomes different components of food and
convert it in the form of:
Q.32 The conjugation of proteins and lipids
with carbohydrates is carried out in: A) Glucose C) NADPH

A) SER C) Golgi apparatus B) ATP D) ADP

B) RER D) Mitochondria Q.39 Animal cells, and cells of some

microorganisms and lower plants
Q.33 Under electron microscope mitochondria contain ________ located near the
appear to be: exterior surface of the nucleus.
A) Vesicles, rods or filaments A) One centriole

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B) Two centrioles Q.45 Each ribosome consists of:

C) Two pairs of centrioles A) Five subunits C) Three subunits
D) Two mitochondria
B) Four subunits D) Two subunits
Q.40 Just before the cell divides: Q.46 Pick up the choice which is true about
A) Chromosomes duplicate subunits of eukaryotic ribosomes:
A) The larger subunits sediments at 60s,
B) Centrioles duplicate while smaller subunits sediments at
C) Ribosomes duplicate 40s.
B) The larger subunit sediments at 50s,
D) Nucleoli duplicate
while smaller subunit sediments at 30s.
Q.41 Centrioles play important role in the: C) The larger subunit sediments at 60s,
A) Cytokinesis of plant cell while smaller subunit sediments at 30s.
D) The larger subunit sediments at 50s,
B) Karyokinesis of plant cell while smaller subunit sediments at 40s.
C) Furrowing during cell division Q.47 Ribosomal subunits are attached to the
mRNA string from:
D) Formation of mitotic apparatus in
plants A) 3- end C) 4- end
B) 2- end D) 5- end
Q.42 Cell contains many tiny granular
structures known as: Q.48 New ribosomes are assembled in the:
A) Nucleus C) Mitochondria
A) Ribosomes C) Mitochondria
B) Nucleolus D) Golgi apparatus
B) Nuclei D) Golgi Apparatus Q.49 The factory of ribosomes is the _______,
Q.43 Ribonucleoprotein particles discovered while that of protein synthesis is the
by Palade in cell are: _______.
A) Nucleolus, ribosomes
A) Ribosomes C) Nucleosomes
B) Nucleus, ribosomes
B) Lysosomes D) Golgi vesicles
C) Ribosomes, nucleolus
Q.44 Ribosomes exist in two forms in D) Nucleolus, mitochondria
eukaryotic cells, i.e.: Q.50 Which one of the following is a single
A) Freely scattered in cytoplasm and membrane enclosed organelle?
attached with SER A) Mitochondria C) Nucleus
B) Freely scattered in cytoplasm and B) Lysosome D) Chloroplast
attached with RER Q.51 Which one of the following is a congenital
disease?
C) Freely scattered in nucleoplasm and
attached with RER A) Uremia

D) Freely scattered in nucleoplasm and B) Glycogenosis

attached with SER C) Myocardial infarction

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D) Cerebral infarction A) Accumulation of lipids in brain cells

Q.52 Which one of the following is not true B) Mental retardation
about Tay sach’s disease? C) Death
A) Mental disorder D) Absence of an enzyme involved in
B) Congenital disorder catabolism of lipids
C) Lysosomal disorder Q.59 Following events are associated with a
lysosomal disorder called Tay Sach’s
D) Cardiovascular disorder disease. Arrange them in a specific
Q.53 Tay sach’s disease is due to deficiency of sequence with respect to their
an enzyme associated with: occurrence:
i. Mental retardation
A) Metabolism C) Catabolism ii. Inheritance of abnormal gene
B) Anabolism D) Catalysis iii. Accumulation of lipids in brain
cells
Q.54 Following organelles are derived from iv. Lack of catabolism of lipids
special assemblies of microtubules, v. Absence of an enzyme
EXCEPT:
A) i, ii, iii, iv, v C) ii, iv, i, iii, v
A) Cilia C) Centrioles
B) v, iv, iii, ii, i D) ii, v, iv, iii, i
B) Flagella D) Microbodies Q.60 Events associated with lysosomal
Q.55 Cyclosis occurs due to the involvement disorders are mentioned here below,
of: arrange them in a sequence with
respect to their occurrence:
A) Microtubules
i. Mutation
B) Microfilaments ii. Storage diseases
C) Intermediate filaments iii. Accumulation of substances
within the cells
D) Myofilaments iv. Deficiency of lysosomal enzymes
Q.56 Intermediate filaments are called so, v. Metabolic sluggishness
because they have intermediate: A) i, ii, iii, iv, v C) v, iv, iii, ii, i
A) Position in cell C) Length B) i, iv, v, iii, ii D) ii, iii, iv, v, i
B) Composition D) Diameter Q.61 Autophagy in a cell is carried out by:
Q.57 Absence of an enzyme that is involved in A) Lysosome C) Glyoxisome
the catabolism of lipids may ultimately
result in: B) Peroxisome D) Mesosome

A) Glycogenosis Q.62 Autophagy is carried out by:

B) Lysosomal disorder A) Lysosomes

C) Mental retardation B) Autophagosomes

D) Storage disease C) Heterophagosomes

Q.58 The most undesirable consequence of D) Peroxisomes

Tay Sach’s disease is:

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Q.63 The organelle that protects the cells

from invading organisms or any other
foreign object is:
A) Lysosome
B) Transport vesicle of endoplasmic
reticulum
C) Golgi vesicle
D) Autophagosome
Q.64 The proteins found in muscles are also
found in:
A) Cytoskeleton C) Endoskeleton
B) Exoskeleton D) Cartilage
Q.65 Cytoskeletal fabric consists of following
structural components EXCEPT:
A) Microtubules
B) Cytosol
C) Microfilament
D) Intermediate filaments
Q.66 Amoeboid movements are because of:
A) Intermediate filaments
B) Microtubules
C) Microfilaments
D) Cytoskeleton
Q.67 Determination of cell shape and
integration of cellular compartments is
the role of:
A) Microfilaments
B) Cell membrane
C) Intermediate filaments
D) Cell wall

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ANSWER KEY (Worksheet-6) Q.2 Answer is “Skeletal Muscle cell”

1 A 21 A 41 C 61 A Explanation: Skeletal muscle cells are
2 D 22 C 42 A 62 B highly elongated and become unwieldy to
3 A 23 B 43 A 63 A be controlled by a single nucleus; thus
4 C 24 A 44 B 64 A contain many nuclei per cell.
5 D 25 D 45 D 65 B
6 C 26 A 46 A 66 C
7 B 27 A 47 D 67 C
8 C 28 A 48 B
9 D 29 A 49 A
10 C 30 A 50 B
11 D 31 C 51 B Q.3 Answer is “Chromatin network,
12 D 32 C 52 D nucleoplasm”
13 A 33 A 53 C
14 B 34 C 54 D Explanation: In non-dividing cell
15 C 35 B 55 B (interphase) DNA of chromosomes have been
16 A 36 A 56 D decondensed and uncoiled. In this form it is
17 B 37 D 57 C called chromatin network. However, during
18 D 38 B 58 C cell division through recondensation and
19 D 39 B 59 D recoiling this chromatin network is
20 C 40 B 60 B converted into discrete structures called
chromosomes. Chromatin network is
EXPLANATION suspended in a fluid substance called
nucleoplasm.
Q.1 Answer is “Irregular, Spherical”
Q.4 Answer is “All activities of cell”
Explanation: Most of the nuclei are
spherical in shape, however nuclei of Explanation: All activities of a cell are
controlled by its genetic material or DNA,
certain cells (like various types of WBCs.)
through the genes; called units of
have irregular shapes e.g. the nucleus of inheritance. Genes are located on
neutrophils is two to five lobed and that of chromosomes.
Esinophil and Basophil is bilobed.
Q.5 Answer is “Nuclear membrane”
Explanation: In eukaryotic cells nuclear
membrane or nuclear envelope separates
the nuclear material from cytoplasm. It is
double membrane having pores inside it.

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Q.6 Answer is “Nuclear pores” Explanation: Number of nucleoli varies

Explanation: Pores are formed by the in different types of diploid cells,
fusion of outer and inner nuclear membranes minimum being one and maximum may be
at certain points which are source of in thousands. It depends upon the
communication between cytoplasm and activeness of cell.
nucleus. Q.11 Answer is “Nucleolus”
Explanation: Nucleoli are factories of
ribosome synthesis whereas, ribosomes
are factories of protein synthesis.
Ribosomes are synthesized and assembled
in nucleoli, then ribosomes synthesize
proteins.
Q.12 Answer is “Chromosomes”
Explanation: Nucleus of a non-dividing
cell contain chromatin material in form of
Q.7 Answer is “Nuclear Pores” network which have been obtained by
Explanation: Nuclear pores are source of uncoiling and decondensation of
chromosomes. As the cell division starts
communication between nucleus and
the chromatin material is
cytoplasm. Cytoplasm is the centre of
recoiled/recondensed to acquire the shape
metabolism for cell and each metabolic
of chromosomes. Chromosomes appear as
activity is controlled by genetic
thread like structures in nucleus at that
information located on chromosomes in
time under microscope.
the nucleus.
Q.13 Answer is “Centromere”
Q.8 Answer is “3-4 nuclear pores / nucleus”
Explanation: Centromere or primary
Explanation: A differentiated cell which
constriction is that part of chromosome
have been assigned a specific role and is
that links sister chromatids or a dyad.
not destined to divide further is less active
During mitosis, spindle fibers are attached
metabolically and need less guidance from
to centromere via the kinetochore.
chromosomes and genes. Thus have less
nuclear pores for communication with Q.14 Answer is “Two sister chromatids”
nucleus. Explanation: Both chromatids of same
Q.9 Answer is “Egg cells” chromosome are sister to each other
Explanation: Egg cell is an whereas they are non-sister to the
undifferentiated cell which undergoes chromatids of other homologue. During
repeated mitoses after fertilization for gametogenesis both sister chromatids are
development and remains highly active. separated and each goes to a separate
That is why it needs much communication gamete. However, in S phase of cell cycle
with nucleus and as a result much number each chromatid synthesizes its sister
of nuclear pores. i.e. upto 30,000 per chromatid again.
nucleus. Q.15 Answer is “Genes”
Q.10 Answer is “one or more per nucleus” Explanation: Genes are physical units of
heredity located on chromosomes.

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Q.16 Answer is “All Individuals of same Explanation: Pollens or microspores are also
species” haploid, formed by meiosis from a diploid
Explanation: The number of microsporocyte or a pollen mother cell.
chromosomes is fixed for a species and The normal diploid number of
any change in it leaves drastic impact on chromosomes in onion is 16.
that individual. Such individuals are Q.23 Answer is “13”
usually abnormal e.g. Down’s syndrome Explanation: Normal diploid number of
with 47 chromosomes and Turner’s chromosomes in frog is 26.
syndrome with 45 chromosomes.
Q.24 Answer is “Endoplasmic reticulum”
Q.17 Answer is “46 chromosomes”
Explanation: Endoplasmic reticulum is a
Explanation: It is normal diploid number source of communication between nucleus
of chromosomes in human being, however of a cell and its external environment.
gametes or germ cells being haploid
Q.25 Answer is “Endoplasmic reticulum”
contain half (23) number of chromosomes.
Explanation: Endoplasmic reticulum
Q.18 Answer is “08” being a network present all around the
Explanation: Drosophila have four pairs nucleus upto cell membrane acts like
of chromosomes i.e. four homologous spokes of a wheel to maintain the shape of
pairs of chromosomes in female the cell.
Drosophila whereas three homologous Q.26 Answer is “ER with ribosomes and ER
pairs and one non homologous pair of without ribosomes”
chromosomes in male Drosophila.
Explanation: ER with ribosomes are
called rough endoplasmic reticulum
(RER) whereas ER without ribosomes is
called smooth endoplasmic reticulum
(SER). Sarcoplasmic reticulum is the SER
of muscle cells.
Q.27 Answer is “Golgi Apparatus”
Explanation: A Golgi body is flattened
membrane bound sac whereas a Golgi
Q.19 Answer is “14”
apparatus is a stack of Golgi bodies,
Explanation: It is normal diploid number whereas as Golgi complex is a Golgi
of chromosomes in garden pea. apparatus along with transport vesicles of
Q.20 Answer is “Haploid” endoplasmic reticulum and Golgi vesicles.
Explanation: As germ cells are products Q.28 Answer is “Maturation face”
of meiosis. Explanation: It is also called trans face
Q.21 Answer is “23 Chromosomes” being away from the endoplasmic
reticulum. From this face transport
Explanation: This is haploid number of vesicles of Golgi bodies are pinched off
human chromosomes as eggs and sperms having finished products inside them. That
are meiotic products. is why it is called maturation face.
Q.22 Answer is “08”
Q.29 Answer is “Ribosomes  RER 
Transport Vesicles of ER  Golgi
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apparatus  Golgi vesicles  Q.31 Answer is “Golgi Apparatus”

Plasma membrane.” Explanation: these granules are actually
Explanation: Raw proteins are golgi vesicles containing digestive
synthesized by ribosomes on RER and enzymes in inactive form, which are
then dumped into cisternae of RER. From activated after being released into
RER these raw proteins are pinched off in duodenum.
transport vesicles of RER. These transport Q.32 Answer is “Golgi Apparatus”
vesicles of RER are fused together at
forming face of Golgi apparatus to form Explanation: All finished products like
golgi bodies. During the movement of conjugated molecules are synthesized in
these golgi bodies from forming face to golgi apparatus after receiving their raw
maturation face these raw proteins are material from endoplasmic reticulum. That
converted into finished products is why golgi apparatus is called finishing,
(conjugated molecules). Then these are packing and distribution section of the
packed in golgi vesicles which are pinched factory of cell. See the figure given at end
off from maturation face. These vesicles of the explanation of question # 30.
move to the cell membrane for exocytosis Q.33 Answer is “Vesicles, rods or filaments”
or secretion as primary lysosomes.
Explanation: Mitochondria may be of rod
shape, vesicle shape or filamentous shape.
Q.34 Answer is “Vary widely”
Explanation: Number of mitochondria
depends upon the activity of the cell.
Similarly shape and internal structure may
also be different in different organisms.
Q.35 Answer is “Mitochondrial matrix”
Explanation: The inner space of
mitochondria within the inner membrane
in which cristae lie is called matrix. The
word matrix indicates that this space is
viscous as compared to relatively aqueous
cytoplasm.

Q.30 Answer is “Forming Face”

Explanation: Blebs from tips of SER are
actually transport vesicles of endoplasmic
reticulum which coalesce together to give
rise to a golgi body at the forming face of
golgi apparatus.

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Q.36 Answer is “F1 particles”

Explanation: These are the knob like tips
of ATP synthase (F. ATPase) embedded in
the thylakoid membrane. The embedded
part of ATP synthase is called F0 particle.

Q.40 Answer is “Centrioles duplicate”

Explanation: Duplication of centrioles is
the first indication of initiation of cell
Q.37 Answer is “Enzymes, Co-enzymes, division in animal cells.
Organic and inorganic salts and DNA
with ribosomes”
Explanation: Mitochondria are power
houses of the cells where two important
phases of aerobic respiration are
accomplished i.e., Krebs cycle and
respiratory electron transport chain. Thus
all enzyme, coenzymes and other
substances related to these pathways are
present in mitochondria. ATPs are Q.41 Answer is “Furrowing during cell
synthesized here. However, some extra division”
chromosomal DNA along with ribosomes
Explanation: In animal cells cytokinesis
are also found in mitochondria.
occurs through furrowing and it starts at the
Q.38 Answer is “ATP” central point between centriole pairs
Explanation: Being power house of the positioned on opposite poles of the dividing
cell mitochondria are involved in synthesis cell.
of most of the energy in the form of ATP
through aerobic respiration i.e. through
Krebs cycle and electron transport chain.
Q.39 Answer is “Two centrioles”
Explanation: Centrioles are located on the
outer surface of nucleus making right
angle with each other in a non-dividing
cell.

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Q.42 Answer is “Ribosomes” Q.46 Answer is “the larger submit sediment

Explanation: Ribosomes are tiny at 60s, while smaller submits sediment
membraneless granular structures of both at 40s”
prokaryotic and eukaryotic cells. Explanation: The larger subunit (60S)
have higher rate of sedimentation as compared
Q.43 Answer is “Ribosomes”
to smaller one (40S), for eukaryotes.
Explanation: Ribosomes are made up of
Q.47 Answer is “5 end”
RNA and proteins. Palade discovered the
ribosomes. Explanation: The genetic message,
transcribed on mRNA is translated in 5 to
Q.44 Answer is “Freely scattered in
cytoplasm and attached with RER” 3 direction.

Explanation: Ribosomes are of two types

with respect to their spatial distribution in
cell i.e., free and attached with membrane
of endoplasmic reticulum. Such
endoplasmic reticulum become rough
surfaced (RER).
Q.48 Answer is “Nucleolus”
Explanation: As nucleolus is the factory
of ribosome synthesis.
Q.49 Answer is “Nucleolus, Ribosomes”
Explanation: Nucleoli synthesize the
ribosomes and in turn ribosomes
synthesize the proteins.
Q.50 Answer is “Lysosomes”
Q.45 Answer is “Two submits” Explanation: Lysosomes have single
Explanation: The larger submit and membrane.
smaller submit.

Q.51 Answer is “Glycogenosis”

Explanation: It is a lysosomal disorder
which is inherited by birth as a genetic
deficiency.
Q.52 Answer is “Cardiovascular disorder”
Explanation: Tay sach’s diseases is a
congenital disorder due to deficiency of a
particular lysosome (enzyme) associated
with catabolism of lipids. As a result,
lipids accumulate in brain and a mental
disorder appears which may lead to death.

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Q.53 Answer is “Catabolism” get accumulated into the brain cells. It will
result in mental retardation.
Explanation: Glyoxisomes contain such
enzymes which are associated with Q.60 Answer is “i, iv, v, iii, ii”
conversion of stored fatty acids to Explanation: When the gene associated
carbohydrates in seedlings of oil yielding with enzyme synthesis is mutated, the
plants. enzyme becomes deficient and as a result
Q.54 Answer is “Microbodies” that metabolic process becomes sluggish
and the substrate (substance) starts
Explanation: Microbodies are cell
organelles like peroxisomes and glyoxisomes. accumulation. This results in storage
disease.
Q.55 Answer is “Microfilaments”
Q.61 Answer is “Lysosome”
Explanation: Microfilaments made up of
contractile actin proteins contract and Explanation: The lysosomes associated
relax rhythmically in a cell and generate a with autophagy or self-eating are called
pumping pressure which forces the autophagosomes. Such lysosomes engulf
cytoplasm to carry out a mass movement some worn out parts of cell and digest it.
or streaming movement in clockwise Q.62 Answer is “Autophagosomes”
manner around the nucleus. It is called
Explanation: Lysosomes associated with
cyclosis.
self-eating (autophagy) are called
Q.56 Answer is “Diameter” autophagosomes.
Explanation: The diameter of
Q.63 Answer is “Lysosome”
intermediate filaments is in-between that
of microtubules and microfilaments. Explanation: Pathogen often hijack
endocytic pathway such as pinocytosis in
Q.57 Answer is “Mental retardation” order to gain entery into the cell. The
Explanation: Due to the deficiency of lysosome prevents easy entery into the cell
such enzymes lipids are accumulated in by hydrolyzing the biomolecules of
the brain cells which lead to mental pathogen necessary for their replication
retardation or even death. Disorder is strategies. Reduced lysosomal activity is
called Tay Sach’s disease. an increase in viral infectivity.
Q.58 Answer is “Death” Q.64 Answer is “Cytoskeleton”
Explanation: The worst consequence of Explanation: Actin, myosin and
the accumulation of lipids in brain is death tropomyosin and other proteins which are
of human being. Even with the best care, part of muscles are also part of
children with infantile Tay Sach’s diease cytoskeleton.
usually die at the age of 4. Q.65 Answer is “Cytosol”
Q.59 Answer is “ii, v, iv, iii, i” Explanation: Cytosol is the soluble or
Explanation: When someone inherits solution part of cytoplasm whereas
abnormal gene associated with the cytoskeleton consists of three components
synthesis of that enzyme required for i.e. microtubules, microfilaments and
catabolism of lipids, the person will lack intermediate filaments.
such enzymes. As a consequence there will Q.66 Answer is “Microfilament”
be no catabolism of lipids and lipids will

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Explanation: Microfilaments are

associated with streaming movement or
mass movement of cytoplasm, called
cyclosis. Any intracellular movement of
cytoplasm is carried out by the rhythmic
contraction of microfilaments and for
pseudopodial movement intracellular
movement of cytoplasm is required.
Q.67 Answer is “Intermediate filament”
Explanation: intermediate filaments are
aggregated on the inner surface of cell
membrane as well as in the space between
cell membrane and nucleus and provide
support to the cell membrane to maintain
its shape on one hand and other hand
maintain the inner compartment of the cell.

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