96 topicwise solved previous year qs cell: the unit of life intracellular digestion of...
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Topicwise Solved Previous Year Qs 96
Cell: The Unit of Life
1. According of fluid mosaic model,
plasma membrane is composed of [1988] (a) phospholipids and oligosaccharides
(b) phospholipids and hemicellulose (c) phospholipids and integral proteins
(d) phospholipids, extrinsic proteins and intrinsic proteins
Solution: (d) According to fluid mosaic model proposed
by Singer and Nicolson (1972, 74), plasma
membrane is composed of phospholipid bilayer and protein. Protein molecules
occur at places both inside and outside of lipid bilayer. The internal proteins are
called intrinsic proteins and the external proteins are called extrinsic proteins.
2. Acetabularia used in Hammerling‘s
nucleocytoplasmic experiments is [1988]
(a) unicellular fungus (b) multicellular fungus
(c) unicellular uninucleate green algae (d) unicellular multinucleate green algae
Solution: (c) Acetabularia used in Hammerling‘s
nucleocytoplasmic experiments is
unicellular uninucleate marine green alga.
3. Organelles can be separated from cell homogenate through [1989]
(a) chromatography (b) X-rays diffraction
(c) differential centrifugation (d) auto-radiography
Solution: (c) Centrifuge is an instrument used to create a centrifugal force. The homogenate of the
cell organelles is allowed to undergo centrifugation by which different cell
organelles get separated. The process is known as differential centrifugation.
4. Plasma membrane is made of [1989]
(a) proteins and carbohydrates
(b) proteins and lipids (c) proteins, lipids and carbohydrates
(d) proteins, some nucleic acid and lipids Solution: (c) Plasma membrane is made up of proteins, lipids and carbohydrates. Carbohydrates
are covalently linked to both lipid and
protein.
5. Polyribosomes are aggregates of [1989]
(a) ribosomes and rRNA (b) only rRNA
(c) peroxisomes (d) several ribosomes held together by
string of mRNA
Solution: (d) Polyribosomes consists of 4-8 ribosomes
which are attached to a single strand of mRNA. This mechanism help in synthesis
of several copies of the same protein.
6. Nucleoproteins are synthesised in
[1989] (a) nucleoplasm
(b) nuclear envelope (c) nucleolus
(d) cytoplasm Solution: (d) Nucleoproteins are conjugated proteins. They are deoxyribonucleoproteins and
ribonucleoproteins synthesised in
cytoplasm of the cell.
7. A bivalent consists of [1989] (a) two chromatids and one centromere
(b) two chromatids and two centromeres (c) four chromatids and two centromeres
(d) four chromatids and four centromeres Solution: (c) A pair of homologus chromosomes lying
together in the zygotene stage of Prophase I of first meiotic division is called a bivalent.
8. Magnification of compound
microscope is not connected with [1990] (a) numerical aperture
(b) focal length of objective
(c) focal length of eye piece (d) tube length
Solution: (a) Magnification is defind as the power of
enlargement. Magnification of compound microscope is the product of magnification
of objective lens and magnification of ocular lens.
9. The latest model for plasma membrane is [1990]
(a) lamellar model
Topicwise Solved Previous Year Qs 97
(b) unit membrane model
(c) fluid mosaic model (d) molecular lipid model
Solution: (c) Fluid mosaic model is the most recent
model of a biomembrane proposed by Singer and Nicolson (1972, 74). According
to this model, the membrane does not have a uniform deposition of lipids which are
present as highly viscous fluid matrix of
two layers of phospholipid moles and proteins arranged in a symetrical pattern.
10. Hammerling‘s experiments of
Acetabularia involved exchanging [1990] (a) cytoplasm
(b) nucleus
(c) rhizoid and stalk (d) gametes
Solution: (c) J. Hammerling (1934) conducted
experiments using two species of green algae Acetabularia crenulata and A.
mediterranea. They differ in the shapes of
their caps. The nucleus in both species is situated in rhizoid at the bottom of stalk. If
after removing cap, stalk of one species is grafted on rhizoid of the other species,
shape of the cap will be determined by nucleus, not by the stalk. This experiment
makes clear that the characters of an individual are controlled by nucleus.
11. Electron microscope has a high resolution power. This is due to [1990,
92] (a) electromagnetic lenses
(b) very low wavelength of electron beam (c) low wavelength of light source used
(d) high numerical aperture of glass lenses used
Solution: (b) The resolution is a power of a microscope to distinguish between two particles that
are closely situated. Electron microscope has high resolution power due to very low
wavelength of electron beam.
12. Resolution power is the ability to [1991]
(a) distinguish two close points (b) distinguish two close objects
(c) distinguish amongst organelles (d) magnify image
Solution: (b) The ability to distinguish two close objects
is called resolution power.
13. Fluid mosaic model of cell
membrane was put forward by [1991] (a) Danielli and Davson
(b) Singer and Nicolson (c) Garner and Allard
(d) Watson and Crick
Solution: (b) Fluid Mosaic Model of cell membrane was
put forward by Singer and Nicolson.
14. Ribosomes were discovered by [1991] (a) Golgi
(b) Porter (c) De Robertis
(d) Palade
Solution: (d) Ribosomes were discovered by Robinson
and Brown in plant cell and palade in animal cell.
15. Cell wall shows [1991]
(a) complete permeability (b) semipermeability
(c) differential permeability
(d) impermeability Solution: (a) Cell wall shows complete permeability because it helps in the transport of
substances in and out of the cell.
16. Addition of new cell wall particles
amongst the existing ones is [1991] (a) deposition
(b) apposition (c) intussusception
(d) aggregation Solution: (c) Growth of cell wall occurs by two methods: (i) Intussusception: When the primary wall
is stretched, the materials of secondary
wall are secreted by protoplam deposited within it. (ii) Apposition: Materials of
secondary wall secreted by protoplam are
Topicwise Solved Previous Year Qs 98
deposited in the form of thin layer one
above the other.
17. Angstrom (Å) is equal to [1992] (a) 0.01 mm
(b) 0.001 mm (c) 0.0001 mm
(d) 0.00001 mm Solution: (c) Angstrom Å = 0.0001 µm 1Å = 10–10 m =
10–8cm = 10–7 mm = 10–4 mm
18. Ribosomes are the centre for [1992] (a) respiration
(b) photosynthesis (c) protein synthesis
(d) fat synthesis
Solution: (c) Ribosomes are the workhouses of protein
biosynthesis, the process of translating messenger RNA (mRNA) into protein. The
mRNA comprises a series of codons that dictate to the ribosome the sequence of the
amino acids needed to make the protein. Using the mRNA as a template, the
ribosome translates each codon of the
mRNA, pairing it with the appropriate amino acid. This is done using molecules of
transfer RNA (tRNA) containing a complementary anticodon on one end and
the appropriate amino acid on the other.Protein synthesis begins at a start
codon near the 5‘ end of the mRNA.
19. Oxysomes of F0 – F1 particles occur
on [1992] (a) thylakoids
(b) mitochondrial surface (c) inner mitochondrial membrane
(d) chloroplast surface Solution: (c) The inner membrane of mitochondria
possess small tennis racket like particles called elementary particle, F0 – F1 particles
or oxysomes. There are 1 × 104 – 1 × 105 oxysomes in a mitochondria.
20. All plastids have similar structure
because they can [1992] (a) store starch, lipids and proteins
(b) get transformed from one type to
another (c) perform same function
(d) be present together
Solution: (b) All plastids are similar in structure. So they can easily get transformed from one
type to another. Depending upon the colours there are three types of plastids-
leucoplasts, chromoplasts and chloroplasts.
21. An outer covering membrane is
absent over [1992]
(a) nucleolus (b) lysosome
(c) mitochondrion (d) plastid
Solution: (a) A covering membrane is absent around
nucleolus. Calcium seems to be essential
for maintaining its configuration.
22. Which one is apparato reticolare? [1992]
(a) Golgi apparatus (b) Endoplasmic reticulum
(c) Microfilaments (d) Microtubules
Solution: (a)
23. Experiments on Acetabularia by Hammerling proved the role of [1992]
(a) cytoplasm in controlling differentiation (b) nucleus in heredity
(c) chromosomes in heredity (d) nucleo-cytoplasmic ratio
Solution: (b) Presence of hereditary information in the nucleus was proved by the work of
Hammerling on single celled alga Acetabularia.
24. Glycogen is a polymer of [1992]
(a) galactose
(b) glucose (c) fructose
(d) sucrose Solution: (b) Glycogen is an animal starch, stored in the liver and is polysaccharide of a-Glucose.
About 30,000 glucose molecules joined by 1-4 a-glycosidic bonds and its branches by
1-6 glycosidic bonds. It gives red colour
with iodine solution. • Galactose is a monosaccharide from milk. • Fructose is a
Topicwise Solved Previous Year Qs 99
monosaccharide from fruit. • Sucrose is a
disaccharide (Glucose + Fructose)
25. Binding of specific protein on regulatory DNA sequence can be studied
by means of [1993] (a) ultra centrifugation
(b) electron microscope (c) light microscope
(d) X-ray crystallography
Solution: (d) X-ray crystallography is a technique to
study the binding of specific protein on regulatory DNA. X-ray crystallography or
single-crystal X-ray diffraction is an analytical technique which uses the
diffraction pattern produced by bombarding
a single crystal with X-rays to solve the crystal structure. The diffraction pattern is
recorded and then analyzed or ―solved‖ to reveal the nature of the crystal. This
technique is widely used in chemistry and biochemistry to determine the structures of
an immense variety of molecules, including inorganic compounds, DNA, and proteins.
26. Names of Schleiden and Schwann are associated with [1993]
(a) protoplasm as the physical basis of life (b) cell theory
(c) theory of cell lineage (d) nucleus functions as control centre of
cell Solution: (b) Cell theory was proposed by Schleiden and
Schwann (1839) according to which ―All living organisms are composed of cells.‖
Cell theory is also known as cell principle, cell doctrine etc.
27. Which is correct about cell theory in
view of current status of our knowledge
about cell structure [1993] (a) It needs modification due to discovery of
subcellular structures like chloroplasts and mitochondria
(b) Modified cell theory means that all living beings are composed of cells capable of
reproducing (c) Cell theory does not hold good because
all living beings (e.g., viruses) do not have
cellular organisation
(d) Cell theory means that all living objects
consist of cells whether or not capable of reproducing
Solution: (c) The exceptions of cell theory is viruses
which do not possess a cellular machinery. They consists of DNA or RNA core
surrounded by a protein sheath and lack cellular organisation.
28. In salivary gland chromosomes/polytene chromosomes,
pairing is [1993] (a) absent
(b) occasional (c) formed between nonhomologous
chromosomes
(d) formed between homologous chromosomes
Solution: (d) In salivary gland chromosomes/ polytene
chromosomes, somatic pairing is formed between homologous chromosomes and
repeated replication of their chromonemata.
29. Cell recognition and adhesion occur due to biochemicals of cell membranes
named [1993] (a) proteins
(b) lipids (c) proteins and lipids
(d) glycoproteins and glycolipids Solution: (d) Cell recognition and adhesion occur due to
biochemicals of cell membranes named glycoproteins and glycolipids. These are
formed due to the small carbohydrate molecules present on lipids and extrinsic
protein.
30. Golgi apparatus is absent in [1993]
(a) higher plants (b) yeast
(c) bacteria and Solution: (c) Golgi complex is absent in prokaryotic cell i.e (PPLO, bacteria and blue green algae). It
is present in all eukaryotic cells except sieve tubes of plants, sperms of bryophytes
and pteridophytes and red blood
corpuscles.
Topicwise Solved Previous Year Qs 100
31. Membranous bag with hydrolytic
enzymes which is used for controlling intracellular digestion of macro -
molecules is [1993, 94] (a) endoplasmic reticulum
(b) nucleosome (c) lysosome
(d) phagosome Solution: (c) Lysosomes are membranous bag with
hydrolytic enzymes which is used for controlling intracellular digestion of macro-
molecules.
32. In plant cells, peroxisomes are associated with [1993]
(a) photorespiration
(b) phototropism (c) photoperiodism
(d) photosynthesis Solution: (a)
In plant peroxisomes are associated with photorespiration. Peroxisomes are
ubiquitous organelles in eukaryotes that function to rid the cell of toxic substances.
They have a single membrane that
separates their contents from the cytosol (the internal fluid of the cell) and that
contains membrane proteins critical for various functions, such as importing
proteins into the organelles and aiding in proliferation. Unlike lysosomes, which are
formed in the secretory pathway, peroxisomes usually self-replicate by
enlarging and then dividing, although there
is some indication that new ones may be formed directly. Peroxisomes were
discovered by the Belgian cytologist Christian de Duve in 1965
33. Balbiani rings (puffs) are sites of
[1993]
(a) DNA replication (b) RNA and protein synthesis
(c) synthesis of polysaccharides (d) synthesis of lipids
Solution: (b) In the region of Balbiani ring the DNA
strands uncoil, become active and produce number of copies of messenger RNA.
34. Inner membrane convolutions of a mitochondrion are known as [1994]
(a) lamellae
(b) thylakoids
(b) grana (d) cristae
Solution: (d) The inner membrane of mitochondria is
infolded to form involutions called cristae. They are meant for increasing the active
area of the inner membrane.
35. Mitochondrial cristae are sites of
[1994] (a) breakdown of macromolecules
(b) protein synthesis (c) phosphorylation of flavoproteins
(d) oxidation-reduction reactions Solution: (d) Mitochondrial cristae possess small
particles called elementary particles which contain ATP- ase. Therefore, they are the
centes of ATP synthesis during oxidative - phosphorylation.
36. Organelle having flattened
membrane bound cisternae and lying near the nucleus is [1994]
(a) golgi apparatus
(b) mitochondrion (c) centriole
(d) nucleolus Solution: (a) Organelle having flattened membrane bound cisternae and lying near the nucleus
is Golgi apparatus.
37. Series of reactions which can
convert fatty acids to sugars in plants but not in animals is [1994]
(a) krebs cycle (b) glyoxylate cycle
(c) ornithine cycle (d) glycolysis
Solution: (b) Several plant structures e.g. pollen, seeds contain fats. The fats are hydrolysed and
consumed as source of energy. This is accomplished through oxidative
degradation called glyoxylate cycle.
38. Auxetic growth is [1994] (a) increase in cell volume only
(b) increase in cell number only
(c) increase in fatty tissue (d) increase in intercellular material
Solution: (a)
Topicwise Solved Previous Year Qs 101
Three types of growth are present in
multicellular animals: (i) Auxetic growth: Increase in cell volume only not in number.
(ii) Multiplication growth: Increase in number not in volume. (iii) Accretionary
growth: Growth is due to mitotic division of some special type of cells occurring in
specific locations of body.
39. The prokaryotic flagella possess
[1995] (a) unit membrane enclosed fibre
(b) protein membrane enclosed fibre (c) ‗9 + 2‘ membrane enclosed structure
(d) helically arranged protein molecule Solution: (d) The prokaryotic flagellum is single
stranded made up of several parallel protein fibrils and helical in shape while in
eukaryotes it is made up of axonema and sheath.
40. The function of rough endoplasmic
reticulum is [1995]
(a) fat synthesis (b) lipid synthesis
(c) protein synthesis (d) steroid synthesis
Solution: (c) Rough endoplasmic reticulum bears
ribosomes on its outer surface. These ribosomes take part in protein synthesis.
41. The point, at which polytene chromosomes appears to be attached
together, is called [1995] (a) centriole
(b) centromere (c) chromomere
(d) chromocentre Solution: (d) Granules of condensed chromatin
(heterochromatin), are found scattered in interphase nuclei. At chromocentre, the
polytene chromosomes appear attached.
42. The desmosomes are concerned with
[1995] (a) cytolysis
(b) cell division (c) cell adherence
(d) cellular excretion Solution: (c) Desmosomes are cementing substances, which adhere to each other and keep the
latter tightly packed and they also prevent
leakage of fluid from interphase.
43. Lysosomes have a high content of [1996, 2000]
(a) hydrolytic enzymes (b) lipoproteins
(c) polyribosomes
(d) DNA ligases Solution: (a) Lysosomes are single membrane bound vesicular organelles rich in acid hydrolases.
They are involved in phagocytosis.
44. Genes located on mitochondrial DNA [1997]
(a) generally show maternal inheritance
(b) are always inherited from the male parent
(c) show biparental inheritance like the nuclear genes
(d) are not inherited Solution: (a) Genes located on the mitochondrial DNA are inherited through the cytoplasm. The
zygote receives cytoplasm from the female
gamete hence it involves maternal inheritance.
45. Some of the enzymes,which are
associated in converting fats into carbhoydrates, are present in [1999]
(a) liposomes
(b) golgi bodies (c) microsomes
(d) glyoxysomes Solution: (d) Golgi bodies are cytoplasmic organelle which take part in elaboration and
secretion of complex biochemicals. Microsomes are small single membraned
cell organelles that absorb oxygen and
perform direct oxidation of substrates. Glyoxisomes contain enzymes for b-
oxidation of fatty acids.
Topicwise Solved Previous Year Qs 102
46. Which of the following organ has single membrane? [1999]
(a) Nucleus (b) Cell Wall
(c) Mitochondria (d) Spherosomes
Solution: (d) Nucleus is enclosed by a double layered
envelope. Sphaerosomes are small
spherical single membrane bound cell organelles specialized to synthesize and
store fat. Mitochondria is also surrounded by a two layered membrane - outer
membrane and inner membrane.
47. The proteins are synthesised at
[1999] (a) ribosomes
(b) mitochondria (c) centrosomes
(d) golgi bodies Solution: (a) Ribosomes are the sites of protein synthesis mitochondria is the site of ATP
synthesis. Golgi complex takes part in
elaboration and secretion of complex biochemicalls. The distinctly staining
region of cytoplasm surrounding the pair of centrioles together with the centrioles is
called centrosome.
48. The cell organelle involved in glyco-sylation of protein is [2000]
(a) ribosome
(b) peroxisome (c) endoplasmic reticulum
(d) mitochondria Solution: (c) Glycosylation is the process or result of addition of saccharides to proteins and
lipids. The process is one of four principal
co-translational and posttranslational modification steps in the synthesis of
membrane and secreted proteins and the majority of proteins synthesized in the
rough ER undergo glycosylation. It is an enzyme-directed site-specific process, as
opposed to the non-enzymatic chemical reaction of glycation.
49. Microtubules absent in [2001] (a) mitochondria
(b) centriole
(c) flagella
(d) spindle fibres Solution: (a) Microtubules are formed of dimers of tubulin. Microtubules are present in
centriole, flagella, spindle fibres but not in Mitochondria.
50. Element necessary for middle
lamella is [2001]
(a) Ca (b) Zn
(c) K (d) Cu
Solution: (a) Zinc is an activator of enzymes like
carbonic anhydrase. Copper takes part in
electron transport as plastocyanin. Potassium maintains membrane
permeability.
51. In fluid mosaic model of plasma membrane [2002]
(a) upper layer is non-polar and hydrophilic (b) upper layer is polar and hydrophobic
(c) phospholipids form a bimolecular layer
in middle part (d) proteins form a middle layer
Solution: (c) Fluid mosaic model of plasma membrane
proposes that plasma membrane comprises of a phospholipid bilayer wherein icebergs
of proteins floating in sea of phospholipids.
52. Which of the following occurs more
than one and less than five in a chromosome? [2002]
(a) Chromatid (b) Chromosome
(c) Centromere (d) Telomere
Solution: (a) A chromatid is one of two identical strands of DNA making up a chromosome that are
joined at their centromeres, for the process of nuclear division (mitosis or meiosis). The
term is used so long as the centromeres remain in contact. When they separate
(during anaphase of mitosis and anaphase 2 of meiosis), the strands are called
daughterchromosomes.The tips of the
chromatid are called telomeres.They are there to prevent the ends of the
chromosome from attaching to other
Topicwise Solved Previous Year Qs 103
chromosomes. It has been said that after
repeated cell replication, the telomeres gets shorter resulting in cell death. Thus, this
mean that the way telomeres work could play a role in determining the lifespan of a
cell.
53. Ribosomes are produced in [2002] (a) nucleolus
(b) cytoplasm
(c) mitochondria (d) golgi body
Solution: (a) Golgi bodies take part in elaboration and
secretion of complex biochemicals. Mitochondria are the site of ATP synthesis.
Ribosomes are produced in nucleolus.
54. Mitotic spindle is mainly composed
of which protein? [2002] (a) Actin
(b) Myosin (c) Tubulin
(d) Myoglobin Solution: (c) Mitotic spindles are composed of
microtubules which are made of tubulin dimers. Actin and myosin are the
contractile proteins of muscle fibres. Myoglobin is oxygen carrying pigment
found in muscle.
55. In which one of the following is nitrogen not a constituent? [2003]
(a) Pepsin
(b) Idioblast (c) Bacteriochlorophyll
(d) Invertase Solution: (b) Raphides are needle-shaped crystals of calcium carbonate or calcium oxalate found
in specialized plant cells called idioblasts. It
is believed that the raphides are a defense mechanism against plant predators, as
they are likely to tear the soft tissues of the throat or esophagus of a plant predator
chewing on the plant‘s leaves. They are non-nitrogenous substances.
56. Flagella of prokaryotic and
eukaryotic cells differ in [2004]
(a) type of movement and placement in cell (b) location in cell and mode of functioning
(c) microtubular organization and type of
movement (d) microtubular organization and function
Solution: (c) Prokaryotes have simple flagella without
microtubules whereas eukaryotes have complex cilia and flagella which consists of
microtubules arranged in 9+2 fashion (an outer ring of nine pairs surrounding 1
center pair). Further in prokaryotes the
arrangement is 9+0.
57. In chloroplasts, chlorophyll is present in the [2004]
(a) outer membrane (b) inner membrane
(c) thylakoids
(d) stroma Solution: (c) The thylakoid membranes possess the chlorophylls. The outer membrane is
permeable to a number of solutes. Inner membrane has a number of carrier
proteins. Stroma forms the matrix containing the enzyme for Calvin cycle.
58. The main organelle involved in modification and routing of newly
synthesized proteins to their destinations is [2005]
(a) chloroplast (b) mitochondria
(c) lysosome (d) endoplasmic Reticulum
Solution: (d) Endoplasmic reticulum transport proteins and enzymes to their destinations i.e.
within the cell and outside the cell.
59. According to widely accepted ―fluid mosaic model‖ cell membranes are semi-
fluid, where lipids and integral proteins
can diffuse randomly. In recent years, this model has been modified in several
respects. In this regard, which of the following statements is incorrect? [2005]
(a) Proteins in cell membranes can travel within the lipid bilayer.
(b) Proteins can also undergo flip-flop movements in the lipid bilayer.
(c) Proteins can remain confined within
certain domains of the membrane. (d) Many proteins remain completely
embedded within the lipid bilayer.
Topicwise Solved Previous Year Qs 104
Solution: (b) Flip-Flop movement is due to migration of lipid molecules from one lipid monolayer to
other monolayer of lipid bilayer.
60. A student wishes to study the cell structure under a light microscope
having 10X eyepice and 45X objective. He should illuminate the object by which
one of the following colours of light so
as to get the best possible resolution? [2005]
(a) Blue (b) Green
(c) Yellow (d) Red
Solution: (a) Resolving power or limit of resolution is the ability of the eye to distinguish two
close objects as separate. Its value is calculated by Abbe‘s equation,
61. Centromere is required for: [2005]
(a) movement of chromosomes towards poles
(b) cytoplasmic cleavage
(c) crossing over (d) transcription
Solution: (a) During anaphase APC (anaphase
promoting complex) develops. It degenerates proteins binding the two
chromatids in the region of centromere. As a result the centromere of each
chromosome divides. This converts the two
chromatids into daughter chromosomes.
62. Protein synthesis in an animal cell occurs [2005]
(a) only on the ribosomes present in cytosol (b) only on ribosomes attached to the
nuclear envelope and endoplasmic
reticulum (c) on-ribosomes present in the nucleolus
as well as in cytoplasm (d) on ribosomes present in cytoplasm as
well as in mitochondria Solution: (d) Protein synthesis in an animal cell occurs on ribosomes present in cytoplasm as well
as in mitcohondria because mitochondria
and chloroplast also have their own DNA, RNA and ribosome so can synthesize half of
their required proteins.
63. Which of the following statement regarding mitochondrial membrane is
not correct? [2006] (a) The enzymes of the electron transfer
chain are embedded in the outer membrane (b) The inner membrane is highly
convoluted forming a series of infoldings (c) The outer membrane resembles a sieve
(d) The outer membrane is permeable to all
kinds of molecules Solution: (a) The enzymes of electron transport system are present in inner mitochondrial
membrane.
64. A major break through in the studies
of cells came with the development of electron microscope. This is because
[2006] (a) the resolving power of the electron
microscope is 200 – 350 nm as compared to 0.1 – 0.2 for the light microscope
(b) electron beam can pass through thick materials, whereas light microscopy
requires thin sections
(c) the electron microscope is more powerful than the light microscope as it
uses a beam of electrons which has wavelength much longer than that of
photons (d) the resolution power of the electron
microscope in much higher than that of the light microscope
Solution: (d) A major break through in cell studies came with the development of EM having great
resolution power due to which we can see the ultrastructures of cell organelles.
65. Select the wrong statement from the
following [2007]
(a) Both chloroplasts and mitochondria have an internal compartment, the
thylakoid space bounded by the thylakoid membrane
(b) Both chloroplasts and mitochondria contain DNA
(c) The chloroplasts are generally much large than mitochondria
(d) Both chloroplasts and mitochondria
contain an inner and an outer membrane. Solution: (a)
Topicwise Solved Previous Year Qs 105
Both chloroplasts and mitochoridria have
an internal compartment, the thylakoid space bounded by double membrane
66. Which one of the following is not a
constituent of cell membrane? [2007] (a) glycolipids
(b) proline (c) phospholipids
(d) cholesterol.
Solution: (b)
67. Keeping in view the fluid mosaic
model for the structure of cell membrane, which one of the following
statements is correct with respect to the
movement of lipids and proteins from one lipid monolayer to the other
(described as flipflop movement)? (a) Both lipids and proteins can flip-flop
(b) While lipids can rarely flip-flop, protein can not
(c) While proteins can flip-flop, lipids can not
(d) Neither lipids, nor proteins can flip-flop
Solution: (b) Keeping in view the ‗Fluid mosaic model‖
for the structure of cell membrane, the movement of lipids and proteins from one
lipid monolayer to the other, lipid can rarely flip-flop, protein can not. The fluid
mosaic model is the most important and widely accepted latest model for plasma
membrane was given by Singer and
Nicolson in 1972. According the them it is ― protein iceberg in a sea of lipids‖.
68. Polysome is formed by
(a) several ribosomes attached to a single mRNA
(b) many ribosomes attached to a strand of
endoplasmic reticulum (c) a ribosome with several subunits
(d) ribosomes attached to each other in a linear arrangement
Solution: (a) Polysome (Polyribosome) is a complex
formed by several ribosomes attached to a single mRNA molecule in the process of
translation.
69. Cellulose is the major component of
cell walls of [2008]
(a) Pythium
(b) Xanthomonas (c) Pseudomonas
(d) Saccharomyces Solution: (a) Cellulose is a major component of cell wall of Pythium. Pythium is a genus of parasitic
Oomycete. Because this group of organisms were once classified as fungi, they are
sometimes still treated as such. Pythium,
like others in the family Pythiaceae, are usually characterized by their production of
coenocytic hyphae, hyphae without separations. Oogonia generally contain a
single Oospore. Antheridia contain an elongated and club shaped antheridium.
70. The two sub-units of ribosome remain united a critical ion level of
[2008] (a) copper
(b) manganese (c) magnesium
(d) calcium
Solution: (c) The two subunits of ribosome remain
united at a critical ion level of magnesium. The presence of magnesium and its amount
plays an important role in the appearance and structure of the ribosomes. If
magnesium is absent in medium, the large particles fall apart to present a group of
smaller particles.
71. Vacuole in a plant cell [2008]
(a) is membrane-bound and contains storage proteins and lipids
(b) is membrane-bound and contains water and excretory substances
(c) lacks membrane and contains air (d) lacks membrane and contains water
and excretory substances
Solution: (b) Vacuole in a plant cell is membrane bound
and contains water and excretory substance. Vacuole is a space within the
cytoplasm of living cell that is filled with
Topicwise Solved Previous Year Qs 106
air, water or other liquid, cell sap or food
particles. In plant cells, there is usually one large vacuole bounded by a single layered
membrane (tonoplast or vacuole membrane); animal cells usually have
several small vacuoles.
72. Plasmodesmata are: [2009] (a) locomotary structures
(b) membranes connecting the nucleus with
plasmalemma (c) connections between adjacent cells
(d) lignified cemented layers between cells Solution: (c) Plasmodesmata are connections between adjacent cells. Plasmodesmata are narrow
channels that act as intercellular
cytoplasmic bridges to facilitate communication and transport of materials
between plant cells. Plasmodesmata are formed during cell division, when traces of
the endoplasmic reticulum become caught in the new wall that divides the parent cell.
73. Cytoskeleton is made up of: [2009]
(a) callose deposits
(b) cellulosic microfibrils (c) proteinaceous filaments
(d) calcium carbonate granules Solution: (c) The cytoskeleton is made up of three kinds of protein filaments actin filaments (also
called microfilaments), intermediate filaments and microtubules whose major
constituents are actin and tubulin
respectively.
74. Stroma in the chloroplasts of higher plant contains: [2009]
(a) light-dependent reaction enzymes (b) ribosomes
(c) chlorophyll.
(d) light– independent reaction enzymes Solution: (d)
Stroma in the chloroplasts of higher plant contains light independent reactions
enzymes. Within the stroma are stacks of thylakoids, the sub-organelles which are
the site of photosynthesis.
75. Middle lamella is composed mainly
of: [2009] (a) muramic acid
(b) calcium pectate
(c) phosphoglycerides
(d) hemicellulose Solution: (b) Middle lamella is mainly composed of calcium pectate. Calcium is deposited in
plants cell walls during their formation - it is required for the stability and function of
cell membranes and acts as a type of ‗cementing agent‘ in the cell walls in the
form of calcium pectate‘. Calcium pectate is
like a glue binding adjacent cells together so if inadequate calcium is not transported
during cell formation, tissues become less stable and prone to disintegration.
76. Which one of the following
structures between two adjacent cells is
an effective transport pathway? [2010] (a) Plasmodesmata
(b) Plastoquinones (c) Endoplasmic reticulum
(d) Plasmalemma Solution: (a) Plasmodesmata are the structure between two adjacent cells that permits the
transport and communication between
them. They are the fine cytoplasmic strands that connect the protoplasts of adjacent
plant cells by passing through the cell walls.
77. Which one of the following has its
own DNA? [2010] (a) Mitochondria
(b) Dictyosome
(c) Lysosome (d) Peroxisome
Solution: (a) Mitochondria has its own DNA. It is as
structure within cytoplasm of eukaryotic cells that carries out aerobic respiration. It
is the site of Kreb‘s cycle and ETS.
Therefore, it is also called as cell‘s energy production site.
78. The main arena of various types of
activities of a cell is: [2010] (a) plasma membrane
(b) mitochondrian (c) cytoplasm
(d) nucleus
Solution: (c) The main arena of various types of
activities of a cell is cytoplasm. It forms the
Topicwise Solved Previous Year Qs 107
living protoplasm of a cell excluding the
nucleus. It consists of proteins, fats, carbohydrates, nucleic acids, vitamins,
waste metabolites and all organelles.
79. The plasma membrane consists mainly of: [2010]
(a) phospholipids embedded in a protein bilayer
(b) proteins embedded in a phospholipid
bilayer (c) proteins embedded in a polymer of
glucose molecules (d) proteins embedded in a carbohydrate
bilayer Solution: (b) Plasma membrane comprises mainly
proteins embedded in a phospholipid bilayer. Protein molecules occur at places
both inside and outer side of the lipid bilayer.
80. Given below is a sample of a portion
of DNA strand. What is so special shown in it? 5‘ —— GAATTC —— 3‘ 3‘ ——
CTTAAG —— 5‘ [2011]
(a) Replication completed (b) Deletion mutation
(c) Start codon at the 5‘ end (d) Palindromic sequence of base pairs
Solution: (d) The sample of a portion of DNA strand
shown in the figure is palindromic sequence of base pairs.
81. Important site for formation of glycoproteins and glycolipids is [2011]
(a) vacuole (b) golgi apparatus
(c) plastid (d) lysosome
Solution: (b) Golgi apparatus is the important site for formation of glycoprotein and glycolipid.
82. Peptide synthesis inside a cell takes
place in: [2011] (a) chloroplast
(b) mitochondria (c) chromoplast
(d) ribosomes
Solution: (d) Peptide synthesis takes place in ribosome
inside a cell.
83. What are those structures that appear as beads - on- string in the
chromosomes when viewed under electron microscope? [2011]
(a) Genes (b) Nucleotides
(c) Nucleosomes (d) Base pairs
Solution: (c) Under electron microscope the nucleosomes appear as beads on string in
chromosome, due to a short length of DNA wrapped around a core of histone proteins.
84. The Golgi complex plays a major role
[NEET 2013]
(a) in digesting proteins and carbohydrates (b) as energy transferring organelles
(c) in post translational modification of proteins and glycosidation of lipids
(d) in trapping the light and transforming it into chemical energy
Solution: (c) Golgi apparatus plays a major role in post
translational modification of proteins
forming glycoprotein and glycosidation of lipid forming glycolipids. A number of
proteins and lipids synthesised on endoplasmic reticulum (rough and smooth
respectively) are modified in the cisternae of the Golgi apparatus before they are
released from it trans face.
85. In mitochondria, proteins
accumulate in the [2011M] (a) outer membrane
(b) inner membrane (c) intermembrane space
(d) matrix Solution: (b) The inner membrane of mitochondria
contains more than 151 different polypeptides, and has a very high protein-
to- phospholipid ration.
86. Which one of the following is not considered as a part of the
endomembrane system? [2011M] (a) Golgi complex
(b) Peroxisome
(c) Vacuole (d) Lysosome
Solution: (b)
Topicwise Solved Previous Year Qs 108
Except peroxisome the remaining three
and ER are the parts of endomembrane system.
87. Ribosomal RNA is actively
synthesized in [2012] (a) Lysosomes
(b) Nucleolus (c) Nucleoplasm
(d) Ribosomes
Solution: (b) Ribosomal RNA is actively synthesized in
nucleolus. Nucleolus is also known as ribosomal factory.
88. Which one of the following does not
differ in E.coli and Chlamydomonas
[2012] (a) Ribosomes
(b) Chromosomal Organization (c) Cell wall
(d) Cellmembrane Solution: (d) Cell membrane of E.coli, a bacteria and Chlamydomonas a unicellular green alga
does not differ. As in both cell membrane is
composed of lipids and proteins.
89. What is true about ribosomes [2012] (a) The prokaryotic ribosomes are 80S,
where ―S‖ stands for sedimentation coefficient
(b) These are composed of ribonucleic acid and proteins
(c) These are found only in eukaryotic cells
(d) These are self-splicing introns of some RNAs.
Solution: (b) Ribosomes are amembraneous (ie. without
membrane) cell organelle composed of rRNA and protein. These are found in both
prokaryotic and eukaryotic cells. In
prokaryotes, ribosomes are 70S type while in eukaryotes, it is 80S type.
90. Nuclear mebrane is absent in [2012]
(a) Penicillium (b) Agaricus
(c) Volvox
(d) Nostoc Solution: (d)
Nostoc is prokaryote while rest are
eukaryotes. Nuclear membrane is absent in prokaryotes.
91. Select the correct statement from
the following regarding cell membrane. [2012]
(a) Na+ and K+ ions move across cell membrane by passive transport
(b) Proteins make up 60 to 70% of the cell
membrane. (c) Lipids are arranged in a bilayer with
polar heads towards the inner part. (d) Fluid mosaic model of cell membrane
was proposed by Singer and Nicolson Solution: (d) Fluid mosaic membrane model was
proposed by Singer and Nicholson in 1972. It is most accepted model of structure of
biomembrane.
92. Which one of the following structures is an organelle within an
organelle? [2012M] (a) Ribosome
(b) Peroxisome
(c) ER (d) Mesosome
Solution: (a) Ribosome are small naked (non membrane
bound) particles made of r-RNA and proteins. Ribosomes are also seen in the
organelles like mitochondria and chloroplasts. They are the cell‘s protein
factories and are found on RER and
scattered in the cytoplasm as polyribosomes. Ribosomes are the sites at
which information carried in the genetic code is converted into protein molecules.
93. Which one of the following cellular
parts is correctly described? [2012M]
(a) Centrioles - Sites for active RNA synthesis.
(b) Lysosomes - Optimally active at a pH of about 8.5.
(c) Thylakoids - Flattened membranous sacs forming the grana of chloroplasts.
(d) Ribosomes - Those on chloroplasts are larger (80s) while those in the cytoplasm
are smaller (70s).
Solution: (c) Centrioles serve as basal bodies for cilia
and flagella. They are concerned with
Topicwise Solved Previous Year Qs 109
spindle formation during cell division.
Lysosomes are membrane-bound organelles containing many hydrolytic enzymes, which
are optimally active at an acid pH (near pH 5). Thylakoids are membrane-bound
organelles found within chloroplasts. The thylakoid membrane, forms many flattened,
fluid-filled tubules that enclose a single convoluted compartment. These tubules
tend to stack on top of each other to forma
structure called a granum.
94. Stroma in the chloroplasts of higher plant contains: [2009]
(a) light-dependent reaction enzymes (b) ribosomes
(c) chlorophyll.
(d) light– independent reaction enzymes Solution: (d) Stroma in the chloroplasts of higher plant contains light independent reactions
enzymes. Within the stroma are stacks of thylakoids, the sub-organelles which are
the site of photosynthesis.
95. The Golgi complex plays a major role
[NEET 2013] (a) in digesting proteins and carbohydrates
(b) as energy transferring organelles (c) in post translational modification of
proteins and glycosidation of lipids (d) in trapping the light and transforming it
into chemical energy Solution: (c) Golgi apparatus plays a major role in post
translational modification of proteins forming glycoprotein and glycosidation of
lipid forming glycolipids. A number of proteins and lipids synthesised on
endoplasmic reticulum (rough and smooth respectively) are modified in the cisternae of
the Golgi apparatus before they are
released from it trans face.
96. A major site for synthesis of lipids is: [NEET 2013]
(a) SER (b) Symplast
(c) Nucleoplasm (d) RER
Solution: (a) The smooth endoplasmic reticulum is the major site for synthesis of lipid. In animal
cells lipid like steroidal hormones are
synthesised in SER.
97. The term ‗glycocalyx‘ is used for [NEET Kar. 2013]
(a) A layer surrounding the cell wall of bacteria
(b) A layer present between cell wall and membrane of bacteria
(c) Cell wall of bacteria
(d) Bacterial cell glyco-engineered to possess N-glycosylated proteins
Solution: (a) Glycocalyx or mucilage is the outermost
coating of bacterial cells/cell wall which is rich in polysaccharides. A thick and
tougher mucilage is called capsule which
gives gummy or sticky trait to cells. It protects the cells from dessication, toxins
and preventing attachment to foreign invaders.
98. Which of the following type of
plastids does not contain stored food material? [NEET Kar. 2013]
(a) Amyloplasts
(b) Chromoplasts (c) Elaioplasts
(d) Aleuroplasts Solution: (b) Chromoplasts are non-photosynthetic coloured plastides which synthesise and
stored carotenoid pigmentes. They, therefore, appear orange red and yellow
where as amyloplast (store starch),
aleuroplast (store proteins) and elaioplast (store oil droplets and fats) are leucoplasts,
colourless plastids.
99. The basic unit of nucleic acid is [1991]
(a) Pentose sugar
(b) Nucleoid (c) Nucleoside
(d) Nucleotide Solution: (d) Nucleic acid (DNA and RNA) comprises of polynucleotides. Each nucleotide consist of
nitrogenous bases, pentose sugar and phosphoric acid.
100. Why is a capsule advantageous to a bacterium? [NEET Kar. 2013]
Topicwise Solved Previous Year Qs 110
(a) It allows the bacterium to attach to the
surface (b) It protects the bacterium from
desiccation (c) It provides means of locomotion
(d) It allows bacterium to ―hide‖ from host‘s immune system
Solution: (d) Capsule is a layer that lies outside the cell
wall of bacteria. The capsule can protect
cells from engulfment by eukaryotic cells, such as macrophages. They also exclude
bacterial viruses and most hydrophobic toxic materials such as detergents.