Cell and Molecular Biology – MCQ Questions with Answers

Cell and Molecular Biology Questions Eduhyme

A structure containing a mass of cytoplasm surrounded by semi-permeable membrane called plasma membrane is called a cell. It encloses cytoplasm, many cell organelles along with nucleus or nuclear material.

On the basis of organization of membranes, variety and structure of cytoplasmic organelles and complexity of nuclear region, the cells are classified into two types:

Prokaryotic cell,
Eukaryotic cell.

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This article provides a list of multiple choice questions with answers used in the study of Cell and Molecular Biology.

1. There is no organized nucleus in:

(a) Bacterial cell
(b) Green algae cell
(c) Animal cell
(d) Plant cell

2. The prokaryotic cells are characterized by:

(a) A distinct nuclear membrane
(b) Absence of chromatin material
(c) Distinct chromosome
(d) Absence of nuclear membrane

3. In a prokaryotic cell, DNA is:

(a) Enclosed by nuclear envelop
(b) Lacking
(c) Not a genetic material
(d) without a membrane

4. Cell wall is found around the:

(a) Prokaryotic cells
(b) Algal cells
(c) Plant cells
(d) All the above

5. Chemical energy of food stuffs is converted into biologically useful forms by:

(a) Ribosomes
(b) Golgi complex
(c) Mitochondria
(d) Plastids

6. Sun radiant energy is converted into chemical energy of organic compound by:

(a) Mitochondria
(b) Chloroplast
(c) Ribosomes
(d) Centrosomes

7. Which structure is present only in animal cell?

(a) Cell membrane
(b) Lysosomes
(c) Centrioles
(d) Ribosomes

8. Single envelope system is characteristic of:

(a) Prokaryotic cell
(b) Eukaryotic cell
(c) None
(d) Both

9. Prokaryote and eukaryotes have the common:

(a) Mitotic apparatus
(b) Histone
(c) Genetic code
(d) Mitochondria

10. Unicellular microscopic organisms were first studied by:

(a) Robert Hooke
(b) Priestley
(c) Pasteur
(d) Leeuwenhoek

11. According to Fluid mosaic model, the correct sequences of substances in plasma lemma is:

(a) L-P-P-L
(b) P-L-L-P
(c) P-P-L-L
(d) L-P-L-P

12. Membrane occurs in:

(a) Chromosomes, nuclei and mitochondria
(b) Cytoplasm, chloroplasts and mitochondria
(c) Cytoplasm, nuclei and starch grains
(d) Chromosomes, chloroplasts and starch grains

13. Plasma membrane is:

(a) Non-selective barrier
(b) Selective barrier
(c) Impermeable
(d) made of cellulose

14. What limits Animal cells from outside?

(a) Cell wall
(b) Basement membrane
(c) Shell membrane
(d) Plasma membrane

15. Cell membrane consists of:

(a) Protein double layer
(b) Phospholipid proteins
(c) Phosphoproteins
(d) Glycoproteins

16. Non-membranous cell organelles are:

(a) Ribosomes
(b) centrioles and ribosomes
(c) E.R.
(d) Mitochondria

17. Which of the following theories explain that plasma membrane is selectively permeable:

(a) Unit membrane theory
(b) Cascade theory
(c) Sandwich theory
(d) Fluid Mosaic theory

18. The hydrophobic ends of phospholipid molecules are:

(a) Polar
(b) Non-polar
(c) Neutral
(d) Bipolar

19. The membrane protein that extend through both sides of lipid bilayer.

(a) Acidic protein
(b) Glycoprotein
(c) Intrinsic protein
(d) Glycolic acid

20. Two plant cells are connected with the help of:

(a) Cell wall
(b) Plasma membrane
(c) Plasmodesmata
(d) None of these

21. Cell’s power houses are its:

(a) Lysosomes
(b) Mitochondria
(c) Ribosomes
(d) Golgi apparatus

22. Mitochondrion is bounded by:

(a) A single unit membrane
(b) Two unit membranes
(c) No membranes
(d) Plasma membranes

23. New mitochondria arise:

(a) De novo
(b) By replication
(c) From plasma membrane
(d) from nuclear envelop

24. The ATPase enzyme is located in the mitochondria in:

(a) Oxysomes
(b) Outer membrane
(c) Inner membranes
(d) Matrix

25. The name mitochondria were given by:

(a) Altman
(b) Flemming
(c) Benda
(d) Kollikar

26. ETS is located in:

(a) Outer mitochondrial membrane
(b) Inter membrane space
(c) Inner mitochondrial membrane
(d) mitochondrial matrix

27. Endoskeleton of the cell is made of:

(a) Endoplasmic reticulum
(b) Mitochondria
(c) Cell Wall
(d) Cytoplasm

28. Metabolic enzymes bringing about synthesis of chemical components of unit membrane in cell occur in:

(a) Rough Endoplasmic reticulum
(b) Smooth Endoplasmic reticulum
(c) Lysosomes
(d) Mitochondria

29. What part of the cell forms the nuclear envelope during telophase?

(a) Cytoskeleton
(b) Centriole
(c) Golgi complex
(d) Endoplasmic reticulum

30. Pores in the cell membrane and outer membrane of nuclear envelope open into:

(a) Golgi apparatus
(b) Mitochondria
(c) ER
(d) Lysosome

31. A ribosome consists of:

(a) Four subunits
(b) Six subunits
(c) Two subunits
(d) three subunits

32. 70S ribosomes are found in:

(a) Prokaryotic cells
(b) Eukaryotic cells
(c) Both of these
(d) None of these

33. Ribosomes are composed of:

(a) rRNA and proteins
(b) rRNA and lipids
(c) rRNA and carbohydrates
(d) Proteins and lipids

34. The 80S ribosomes of eukaryotes break into:

(a) 50S and 30S
(b) 40S and 40S
(c) 60S and 40S
(d) 60S and 50S

35. Ribosome was discovered by:

(a) Kollicker
(b) Palade
(c) de Duve
(d) Porter

36. Ribosome helps in:

(a) Lipogenesis
(b) Cellular digestion
(c) Protein synthesis
(d) Photosynthesis

37. Golgi apparatus occurs in:

(a) Bacteria
(b) Human RBC
(c) All the cells
(d) All the cells except bacteria and RBC

38. Dictyosome is called:

(a) Lysosome
(b) Mitochondria
(c) Golgi body
(d) Ribosome

39. Cell secretion is carried out by:

(a) Nucleolus
(b) Plastids
(c) E.R.
(d) Golgi complex

40. Materials enter Golgi complex at:

(a) Cis region
(b) Medial region
(c) Trans region
(d) Trans Golgi reticulum

41. Proteins are modified in:

(a) ER
(b) Golgi complex
(c) Both a and b
(d) Neither in a nor in b

42. Lysosomes arise from:

(a) Smooth ER
(b) Golgi complex
(c) Both of these
(d) None of these

43. Autophagic vesicles digest:

(a) Pinosome contents
(b) Cell organelles
(c) Phagosome contents
(d) Micro-organisms

44. Lysosome was discovered by:

(a) de Duve
(b) Robert Brown
(c) Hooke
(d) Robinson

45. Lysosomes are considered suicide bags because they contain:

(a) Parasitic activity
(b) Food vacuole
(c) Catabolic enzymes
(d) Hydrolytic enzymes

46. The pattern of organization in centriole is:

(a) 9 + 0
(b) 9 + 1
(c) 9 + 2
(d) 9 + 3

47. Centriole occurs:

(a) Singly
(b) In pairs
(c) In threes
(d) In fours

48. Function of centriole is related with:

(a) Initiation of cell division
(b) Formation of cell plate
(c) Formation of spindle fibers
(d) Formation of nucleolus

49. Microtubules in cilia and flagella are formed of:

(a) Actin
(b) Myosin
(c) Elastin
(d) Tubulin

50. Arms of A sub-units are composed of:

(a) Tubulin
(b) Actin
(c) Myosin
(d) Dynein

51. The supporting framework of a cell consists of:

(a) Microtubules
(b) Intermediate filament
(c) Microfilaments
(d) All the above

52. Nucleus is separated from cytoplasm by nuclear membrane which is:

(a) Double, non-porous
(b) Single, non-porous
(c) Single, porous
(d) Double, porous

53. Nucleolus is especially rich in:

(a) DNA and proteins
(b) DNA and lipids
(c) RNA and proteins
(d) RNA and lipids

54. Nuclear membrane facilitates:

(a) Synapses of homologous chromosomes
(b) Nucleocytoplasmic exchange of materials
(c) Anaphasic separation of daughter chromosomes
(d) Organization of spindles

55. Nucleoplasm is continuous with cytoplasm through:

(a) Centriole
(b) Nucleopores
(c) E.R.
(d) Golgi Body

56. The major component of the nucleus is:

(a) DNA
(b) RNA
(c) Lipids
(d) Proteins

57. Chief role of nucleolus in a nucleus concerns:

(a) Organization of chromosomes
(b) DNA replication
(c) Ribosomal synthesis
(d) Chromatid separation

58. Nucleus was discovered by:

(a) Robert Brown
(b) Robert Hook
(c) Virchow
(d) De Duve

59. Nucleolar organizer is associated with:

(a) Synthesis of plasma membrane
(b) Ribosome formation
(c) G6PD
(d) Disappearance of nuclear membrane

60. Chromosomes are best seen in:

(a) Interphase
(b) Metaphase
(c) Prophase
(d) Telophase

61. A chromosome with terminal centromere is called:

(a) Metacentric
(b) Telocentric
(c) Submetacentric
(d) Acrocentric

62. A chromatid has:

(a) One chromonema
(b) Four chromonemata
(c) Two chromonemata
(d) numerous chromonemata

63. In bacterial chromosomes, nucleic acid polymers are:

(a) Linear RNA molecule
(b) Linear DNA molecule
(c) Two types of DNA and RNA
(d) Circular DNA molecule

64. The component of chromosomes that controls heredity is:

(a) Proteins
(b) RNA
(c) DNA
(d) Metal ions

65. In which of the following organisms were discovered polytene chromosomes?

(a) Musca
(b) Cimex
(c) Drosophila
(d) Chironomus

66. Lampbrush chromosomes are found during:

(a) Interphase
(b) Metaphase of meiosis
(c) Prophase of mitosis
(d) First prophase of meiosis

67. Balbiani rings occur in:

(a) Polytene chromosomes
(b) Lampbrush chromosomes
(c) Polysomes
(d) Heterosomes

68. Chromosomes with equal arms are called:

(a) Submetacentric
(b) Metacentric
(c) Telocentric
(d) Acrocentric

69. An octamer of four histones complexed with DNA is called:

(a) Nucleosome
(b) Centrosome
(c) Chromosome
(d) Endosome

70. The proper sequence of cell cycle is:

(a) S, M, G1, G2
(b) M, G1, G2, S
(c) S, G1, G2, M
(d) G1, S, G2, M

71. Karyokinesis refers to the division of:

(a) Cytoplasm into two
(b) Nucleus into two
(c) Protoplasm into two
(d) none of them

72. The spindle fibers attach chromosomes with:

(a) Chromo center
(b) Centriole
(c) Kinetochore
(d) Telocentric

73. Who proposed the term mitosis?

(a) Farmer and Moore
(b) Flemming
(c) Nigeli
(d) Brown

74. Chromosomes reach equator during cell division at:

(a) Prophase
(b) Metaphase
(c) Anaphase
(d) Telophase

75. Mitosis occurs in:

(a) Roots
(b) Shoots
(c) Germ cells
(d) Somatic cells

76. Nuclear membrane disappears at which stage:

(a) Metaphase
(b) Anaphase
(c) Early prophase
(d) late prophase

77. Chromosomes move towards different poles, during cell division, due to:

(a) Centrioles
(b) Vacuoles
(c) Cytokinesis
(d) Microtubules

78. In cell cycle DNA replication takes place in:

(a) M-phase
(b) S-phase
(c) G1 -phase
(d) G2-phase

79. Anaphase of mitosis differs from metaphase in:

(a) Half the number of chromosomes
(b) Half the number of chromatids in each chromosome
(c) Half the number of chromosomes but doubles the number of chromatids in each chromosome
(d) Half the number of chromosomes and half the number of chromatids in each chromosome.

80. Synaptonemal complex is associated with:

(a) Mitotic chromosomes
(b) Paired meiotic chromosomes
(c) Lampbrush chromosomes
(d) polytene chromosomes

81. The term meiosis was coined by:

(a) Leeuwenhoek
(b) Beadle and Tatum
(c) Hooke and Brown
(d) Farmer and Moore

82. During meiosis exchange of paternal and maternal chromosomes is called:

(a) Recombination
(b) Linkage
(c) Segregation
(d) Crossing over

83. Crossing over and unzipping of homologous chromosomes in meiosis occurs at:

(a) Diplotene
(b) Pachytene
(c) Zygotene
(d) Leptotene

84. Synapsis occurs during:

(a) Leptotene
(b) Zygotene
(c) Pachytene
(d) Diplotene

85. Crossing over occurs at:

(a) One stranded stage
(b) Two stranded stage
(c) Three stranded stage
(d) four stranded stage

86. Advantage of crossing over is that it causes:

(a) Linkage
(b) Stability
(c) Inbreeding
(d) Variation

87. At the end of first meiotic division, number of chromosomes is:

(a) Halved
(b) Doubled
(c) Remains same
(d) tripled

88. Second meiotic division results:

(a) Separation of homologous chromosomes
(b) Separation of chromatids and centromeres
(c) Synthesis of fresh DNA
(d) Separation of sex chromosomes

89. Anaphase in second meiotic division is characterized by:

(a) Separation of non-homologous chromosomes
(b) Separation of homologous chromosomes
(c) Separation of chromatids
(d) All of them

90. Mutation means:

(a) Any change in organism
(b) Any non inheritable genetic change
(c) Any environmental induced change in genes
(d) A genetic change, natural of induce but inheritable

91. Wobble Hypothesis is applicable to:

(a) Entire codon of mRNA
(b) Second nucleotide of a codon on mRNA
(c) First nucleotide of a codon
(d) Third nucleotide of a codon

92. If mutation cause a change in nucleotide of a codon at 3rd position, it results into:

(a) Entire defective protein chain translation
(b) No translation of mRNA at all
(c) No change in translational product
(d) Except for that amino acid, rest of the polypeptide chain will be normal

93. Codons are made of 3 nucleotides, so the codon is called as:

(a) Triplet
(b) Singlet
(c) Uniform
(d) Triple

94. The main feature of codons are:

(a) These are triplet and continuous
(b) These are universal and made of deoxyribonucleotides
(c) Present on DNA are translate into polypeptide
(d) Present on RNA

95. The initiation codon is:

(a) AUG
(b) AUG or GUG
(c) UUA
(d) UUA, UAG or UGA

96. Some of the codons are degenerate in nature, it means:

(a) At the time of translation they disintegrate into nucleotides
(b) More than one codon can code for same amino acid
(c) Same codon can code for more than one amino acid
(d) None of the above

97. The termination of translation occur, when the codon ready for translation is:

(a) AUG
(b) AUG or GUG
(c) UUA
(d) UUA, UAG or UGA

98. For translating a codon, its corresponding anticodon is present on:

(a) mRNA
(b) tRNA
(c) rRNA
(d) All of them

99. The reading of codon starts from:

(a) 5’ end
(b) 3’ end
(c) Any end
(d) Anywhere in between

100. DNA is acidic due to the presence of:

(a) Nitrogen bases
(b) Sugar
(c) Phosphate group
(d) double helix structure

101. DNA double helix model was proposed by

(a) Watson
(b) Watson and Franklin
(c) Franklin and Crick
(d) Watson and crick

102. Double Helix model of DNA was based on the observations of:

(a) Watson
(b) Wilkins and Franklin
(c) Franklin and Crick
(d) Watson and crick

103. DNA replication is:

(a) Dispersive
(b) Conservative
(c) Non conservative
(d) Semi conservative

104. DNA replication enzyme is:

(a) DNA Gyrase
(b) DNA polymerase
(c) Restriction Endonuclease
(d) all of these

105. Who proposed the concept of transformation?

(a) Hershey and Chase
(b) Griffith
(c) Avery, Macleod, and Mc Carty’s
(d) none of these

106. Who proved chemical basis of transformation?

(a) Harshey and Chase
(b) Griffith
(c) Avery, Macleod and Mc Carty’s
(d) Watson and Crick

107. Recombinant DNA technology is primarily based of the discovery of which enzyme?

(a) DNA Polymerase
(b) DNA Ligase
(c) DNA Endonuclease
(d)) DNA Restriction Endonuclease

108. Vector in RNA recombinant Technology helps in:

(a) Infecting host cell with bacteria
(b) Transferring target DNA in host cell
(c) Transferring desired gene for recombination
(d) transferring any type of DNA in host
cell

109. When E.coli is cultured in N15, for two cell cycles, how many DNA molecules of DNA after two cycles will have heavy N:

(a) All but 2 molecules will be pure heavy
(b) All but no molecules will be pure heavy
(c)All DNA molecules will have N15
(d) 50% heavy and 50% light

110. On the basis of functions RNA is of _________ types:

(a) 2
(b) 3
(c) 1
(d) 4

111. Formation of RNA from DNA is called as:

(a) Replication
(b) Duplication
(c) Transcription
(d) Translation

112. The genetic material of some of the viruses is constituted of:

(a) Protiens
(b) Ribonucleic acid
(c) Deoxyribonucleic acid
(d) Any of these

113. t-RNA acts as an:

(a) Adaptor molecule
(b) molecule to transfer amino acids to the site of protein synthesis
(c) Soluble RNA
(d) all of these

114. The genetic information of protein synthesis is carried by:

(a) RNA
(b) r-RNA
(c) m-RNA
(d) t-RNA

115. Amino acid is attached to tRNA by its _______ arm:

(a) Anticodon arm
(b) 3’end of arm opposite to anticodon arm
(c) Any arm
(d) DHU arm

116. r-RNA formation takes place in:

(a) Cytoplasm
(b) Nucleus
(c) Nucleolus
(d) Golgi body

117. Eukaryotic ribosomes are of ________ S, having smaller and bigger unit made of _______ and _________ S.

(a) 70S, 30S & 40S
(b) 70S, 30S & 50S
(c) 80S, 50S &30S
(d) 80S, 60S & 40S

118. Codons are present on:

(a) DNA
(b) RNA
(c) t-RNA
(d) mRNA

119. Clover leaf shape is attained by _______ molecule after maturation:

(a) t-RNA
(b) m-RNA
(c) r-RNA
(d) DsDNA

120. Transcript is:

a) A chain of ribonucleotides
b) Any type of RNA
c) The copy of DNA template
d) All the above

121. RNA formation takes place in:

a) Cytoplasm
b) Nucleus
c) Golgi complex
d) Endoplasmic reticulum

122. In eukaryotic cell, transcription occurs in:

a) Nucleus
b) Mitochondria
c) Plastids
d) All the above

123. In prokaryotes, transcription of all three types of RNAis controlled by:

a) RNA Polymerase
b) RNA Polymerase-I
c) RNA Polymerase-II
d) RNA Polymerase-III

124. MRNA in eukaryotic cell is transcribed by:

a) RNA Polymerase
b) RNA Polymerase-I
c) RNA Polymerase-II
d) RNA Polymerase-III

125. Bigger subunit of ribosomes has—- sites:

a) 2
b) 3
c) 1
d) 4

126. Operon model of regulation of translation was proposed by:

a) Watson
b) Crick
c) Jacob
d) Morgan

127. In Lac-operon model, —— acts as inducer to switch on operon:

a) Galactose
b) Permease
c) Lactose
d) None of the above

128. The expressible part of hnRNA are:

a) mRNA
b) Exons
c) Introns
d) Cistrons

129. Which enzyme helps in the loading and activation of tRNA?

a) Ribozyme
b) Peptidyl transferase
c) Aminoacyl synthetase
d) RNA polymerase

Correct Answers –

Fill in the Blanks –

Two types of nucleic acids differ from each other in _____________ as well as _____________.
DNA and RNA has similar _____________ but different _____________.
Any types of DNA molecules will always follow _____________ rule, which states that total amount of — are always equal to the total amount of _____________.
While proving the chemical responsible for transformation of bacteria, _____________ enzyme was used to prove it as it could digest _____________ which was found responsible for causing transformation while other enzymes like _____________, _____________ and _____________ were found ineffective.
Endonuclease can cut DNA from _____________ site but restriction Endonuclease at some _____________ sites also called as _____________ sequences.
Prokaryotic replication proceeds in _____________ direction from _____________.
Most commonly DNA occurs as a _____________ helix.
Replication is the process of formation of _____________.
t- RNA has a special shape, called as _____________ and helps in carrying amino acids from _____________ to the _____________ of protein synthesis.
RNA plays the role of both _____________ and _____________ genetic molecule.
RNA may also act as a functional molecule by acting as _____________.
m-RNA carries _____________ information from nucleus to _____________ for _____________ synthesis.
m-RNA of eukaryotic cell undergoes processing by _____________ and _____________.
RNA is the genetic material of _____________.
The three dimensional structure of tRNA was proposed to L-shaped by _____________.
t-RNA synthesized by _____________ in eukaryotes.