Practice Quiz On Cell Structure And Function online biology quiz on cell structure and function to gain complete knowledge of general science for competitive exams. Following are the MCQ for your practice.

1. A major site for synthesis of lipids is

(a) Symplast

(b) Nucleoplasm

(c)RER

(d) SER

Ans: (d) SER

2. Select the correct statements from the following regarding cell membrane.

(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

Ans:  (d) Fluid mosaic model of cell membrane was proposed by Singer and Nicolson

3. Which one of the following cellular parts is correctly described?

(a) Thylakoids – flattened membranous sacs forming the grana of chloroplasts

(b) Centrioles – sites for active RNA synthesis

(c) Ribosomes – those on chloroplasts are larger (80S) while those in the cytoplasm are smaller (70S)

(d) Lysosomes – optimally active at a pH of about 8.5

Ans: (a) Thylakoids – flattened membranous sacs forming the grana of chloroplasts

4. Select the wrong statement from the following.

(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 larger than mitochondria

(d) Both chloroplasts and mitochondria contain an inner and an outer membrane

Ans: (a) Both chloroplasts and mitochondria have an internal compartment, the thylakoid space bounded by the thylakoid membrane

5. Which of the following statements regarding cilia is not correct?

(a) Cilia contain an outer ring of nine doublet microtubules surrounding two singlet microtubules

(b) The organized beating of cilia is controlled by fluxed of Ca²⁺ across the membrane

(c) Cilia are hair like cellular appendages

(d) Microtubules of cilia are composed of Tubulin

Ans: (b) The organized beating of cilia is controlled by fluxed of Ca²⁺ across the membrane

6. A major breakthrough in the studies of cells came with the development of electron microscope. This is because

(a) 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.

(b) The resolving power of the electron microscope is much higher than that of the light microscope

(c) The resolving power of the electron microscope is 200-350 nm as compared to 0.1-0.2 nm for the light microscope

(d) Electron beam can pass through thick materials, whereas light microscopy requires thin sections

Ans: (b) The resolving power of the electron microscope is much higher than that of the light microscope

7. 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 correct?

(a) Proteins in cell membranes can travel within the lipids bilayer

(b) Proteins can also undergo flip-flop movements in the lipid bilayer

(c) Proteins can remain confined within certain domains of the menbrane

(d) Many proteins remain completely embedded within the lipid bilayer

Ans: (b) Proteins can also undergo flip-flop movements in the lipid bilayer

8. Centromere is required for

(a) Movement of chromosomes towards poles

(b) Cytoplasmic Cleavage

(c) Crossing Over

(d) Transcription

Ans: (a) Movement of chromosomes towards poles

9. In chloroplast, chlorophyll is present in the

(a) Outer Membrane

(b) Inner Membrane

(c) Thylakoids

(d) Stroma

Ans: (c) Thylakoids

10. Proteinaceous pigment which controls the activities concerned with light is

(a) Phytochrome

(b) Chlorophyll

(c) Anthocyanin

(d) Carotenoids

Ans: (a) Phytochrome

11. When water moves through a semipermeable membrane then which of the following pressure develops?

(a) Osmotic Pressure

(b) Suction Pressures

(c) Turgor Pressure

(d) Wall Pressure

Ans: (a) Osmotic Pressure

12. Which of the following ribosomes are engaged in protein synthesis in animal cell?

(a) Ribosomes which occur on nuclear membrane and E.R

(b) Ribosomes of only Cytosol

(c) Ribosomes of only Nucleolus ad Cytosol

(d) Ribosomes of only Mitochondria and Cytosol

Ans: (a) Ribosomes which occur on nuclear membrane and E.R

13. Function of telomeres in nucleus is

(a) Poleward Movement

(b) To Initiate the RNA synthesis

(c) To Seal the ends of Chromosome

(d) ToRecognise the Homologous Chromosome

Ans: (c) To Seal the ends of Chromosome

14. Which cell organelle is concerned with glycosylation of protein?

(a) Ribosome

(b) Peroxisome

(c) EndoplasmicReticulum

(d) Mitochondria

Ans: (c) EndoplasmicReticulum

15. Which of the following organelles has single membrane?

(a) Mitochondria

(b) Spherosomes

(c) Nucleus

(d) Cell Wall

Ans: (b) Spherosomes

16. Which of the following structures will not be common to mitotic cell of a higher plant?

(a) Centriole

(b) Spindle Fibre

(c) Cell Plate

(d) Centromere

Ans: (a) Centriole

17. Protein synthesis in an animal cell, takes place

(a) In the cytoplasm as well as endoplasmic reticulum

(b) Only on ribose attached to nucleon

(c) Only in the cytoplasm

(d) In the nucleolus as well as in the cytoplasm

Ans: (d) In the nucleolus as well as in the cytoplasm

18. The prokaryotic flagella possess

(a) Helically arranged protein molecule

(b) 9+2 membrane enclosed structure

(c) Unit membrane enclosed fibre

(d) Protein membrane enclosed fibre

Ans: (a) Helically arranged protein molecule

19. Which of the following organelles contains enzymes that have digestive actin?

(a) Ribosomes

(b) Polysomes

(c)Plastids

(d) Lysosomes

Ans: (d) Lysosomes

20. In mitochondria, Cristae act as sites for

(a) Protein Synthesis

(b) Phosphorylation of Flavoproteins

(c) Breakdown of Macromolecules

(d) Oxidation Reduction Reaction

Ans: (d) Oxidation Reduction Reaction

21. Which one of the following organelles is located near the nucleus and contains a collection of flattened membrane bound cisternae?

(a) Nucleolus

(b) Mitochondrion

(c) Centriole

(d) Golgi Apparatus

Ans: (d) Golgi Apparatus

22. The inner membrane of the mitochondria is usually, highly convoluted forming a series of infolding known as

(a) Thylakoids

(b) Lamellae

(c) Cristae

(d) Grana

Ans: (c) Cristae

23. Besides giving out secretory vesicles, the Golgiapparatus is also concerned with the formation of

(a) Lysosomes

(b) Plastids

(c) Grana of Chioroplasts

(d) Cell Plates after Cell Division in Plants

Ans: (a) Lysosomes

24. Golgiapparatus is absent in

(a)Higher Plants

(b) Yeast

(c) Bacteria and Blue-Green Algae

(d) None of these

Ans: (c) Bacteria and Blue-Green Algae

25. Experiments of Acetabularia by Hammerling proved the role of

(a) Cytoplasm in controlling differentiation

(b) Nucleus in Heredity

(c) Chromosomes in Heredity

(d) Nucleo-cytopalsmic Ratio

Ans: (b) Nucleus in Heredity

26. An outer covering membrane is absent over

(a) Nucleolus

(b) Lysosome

(c) Mitochondrion

(d) Plastid

Ans: (a) Nucleolus

27. All plastids have similar structure because they can

(a) Store starch, lipids and proteins

(b) Get transformed from one type of another

(c) Perform same function

(d) Be present together

Ans: (b) Get transformed from one type of another

28. Oxysomes of F0 – F1 particles occur on

(a) Thylakoids

(b) Mitochondrial Surface

(c) Inner Mitochondrial Membrane

(d) Chloroplast Surface

Ans: (c) Inner Mitochondrial Membrane

29. Electron microscope has a high resolution power. This is due to

(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

Ans: (b) Very low wavelength of electron beam

30. Addition of new cell wall particles amongst the existing one is

(a) Deposition

(b) Apposition

(c) Intussusception

(d) Aggregation

Ans: (c) Intussusception

31. Resolution power is the ability to

(a) Distinguish two close points

(b) Distinguish two close objects

(c) Distinguish amongst organelles

(d) Magnify image

Ans: (b) Distinguish two close objects

32. Nucleoproteins are synthesised in

(a) Nucleoplasm

(b) Nuclear Envelope

(c) Nucleolus

(d) Cytoplasm

Ans: (d) Cytoplasm

33. Acetabularia used in Hammerling’s nucleo-cytoplasmic experiments is

(a) Unicellular Fungus

(b) Multicellular Fungus

(c) Unicellular uninucleate green algae

(d) Unicellular multinucleate green algae

Ans: (c) Unicellular uninucleate green algae

34. Microtubules do not occur in

(a) Mitochondria

(b) Centrioles

(c) Spindle Fibres

(d) Flagella

Ans: (a) Mitochondria

35. Ribosomes are granules formed of

(a) rRNA + tRNA

(b) mRN A+ tRNA

(C) rRNA + proteins

(d) mRNA+proteins

Ans: (C) rRNA + proteins

36 . Which one is present nearest to plasma membrane

(a)Middle Lamella

(b) Primary Wall

(c) Secondary Wall

(d) Tonoplast

Ans: (c) Secondary Wall

37. Welded areas between adjacent cells are

(a) Desmosomes

(b) Gap Junctions

(c) Intercellular Bridges

(d) Inter Digitations

Ans: (a) Desmosomes

38. Chlorophyll occurs in chloroplast

(a) Inner Membrane

(b) Thylakoid Membranes

(c) Outer Membrane

(d) Stroma

Ans: (b) Thylakoid Membranes

39. Which is common in plant and animal cells

(a) Centrioles

(b) Central Vacuole

(c) Mitochondria

(d) Plastids

Ans: (c) Mitochondria

40. Which is not a function of vacuole in plant cell?

(a) Formation of H₂O₂

(b) Waste Disposal

(c) Cell Elongation

(d) Storage

Ans: (a) Formation of H₂O₂

41. Arrangement of microtubules is

(a) 9+9

(b) 9+3

(c) 9+4

(d) 9+2

Ans: (d) 9+2

42. Lysosomes are produced by

(a Mitochondria

(b) Endoplasmic Reticulum

(c) Golgi Bodies

(d) Leucoplasts

43. Which does not occur in cell membrane

(a) Glycolipids

(b) Proline

(c) Phospholipids

(d) Cholesterol

Ans: (a) Glycolipids

44. Subunits of 80 S ribosomes are

(a) 40S

(b) 60S

(c) 40S-60S

(d) None of these

45. Vacuole of plant cells

(a) Lacks Membrane, contains water and excretory substances

(b) Is membrane bound, contains water and excretory substances

(c) Is membrane bound, contains storage proteins and lipids

(d) Lacks membrane and contains air

Ans: (b) Is membrane bound, contains water and excretory substances

46. What is true of membrane lipids and proteins?

(a) None can flip-flop

(b) Both can flip-flop

(c) Proteins can flip-flop but lipids cannot

(d) Lipids can rarely flip-flop but proteins cannot

Ans: (d) Lipids can rarely flip-flop but proteins cannot

47. Middle lamella is mainly composed of

(a) Calcium Pectate

(b) Phosphaglycerides

(c) Muramic Acid

(d) Hemicellulose

Ans: (a) Calcium Pectate

48. Who first saw and described a live cell

(a) Matthias Schleiden

(b) Theodore Schwann

(c) Anton Von Leeuwenhock

(d) Rudolf Virchow

Ans: (c) Anton Von Leeuwenhock

49. Plasma membrane consists mainly of

(a) Proteins Embedded in a phospholipid bilayer

(b) Protein embedded in a polymer of glucose molecule

(c) Proteins embedded in a carbohydrate bilayer

(d) Phospholipids embedded in protein bilayer

Ans: (a) Proteins Embedded in a phospholipid bilayer

50. Animal cells do not possess

(a) Plasmodesmata

(b) Centriole

(c) 80 S Ribosomes

(d) All of these

Ans: (a) Plasmodesmata