MCQ The Fundamental Unit of Life
1. Which of the following can be made into crystal?
(a) A Bacterium
(b) An Amoeba
(c) A Virus
(d) A Sperm
Ans. (c) A Virus
Explanation: Virus does not have a cell; like other options. Virus is composed of nuclear material enclosed in a protein coat. Due to this, it can be into crystal.
2. A cell will swell up if
(a) The concentration of water molecules in the cell is higher than the concentration of water molecules in surrounding medium
(b) The concentration of water molecules in surrounding medium is higher than water molecules concentration in the cell
(c) The concentration of water molecules is same in the cell and in the surrounding medium
(d) Concentration of water molecules does not matter
Ans. (b) The concentration of water molecules in surrounding medium is higher than water molecules concentration in the cell
Explanation: If concentration of water molecules in surrounding medium is higher than water molecules concentration in the cell, it will result in movement of water into the cell. This will result in cell getting swelled up.
3. Chromosomes are made up of
(a) DNA
(b) protein
(c) DNA and protein
(d) RNA
Ans. (c) DNA and protein
4. Which of these options are not a function of Ribosomes?
(i) It helps in manufacture of protein molecules
(ii) It helps in manufacture of enzymes
(iii) It helps in manufacture of hormones
(iv) It helps in manufacture of starch molecules
(a) (i) and (ii)
(b) (ii) and (iii)
(c) (iii) and (iv)
(d) (iv) and (i)
Ans. (c) (iii) and (iv)
Explanation: Ribosomes are responsible for protein synthesis. Enzymes are composed of protein. Hence, options (iii) and (iv) are incorrect.
5. Which of these is not related to endoplasmic reticulum?
(a) It behaves as transport channel for proteins between nucleus and cytoplasm
(b) It transports materials between various regions in cytoplasm
(c) It can be the site of energy generation
(d) It can be the site for some biochemical activities of the cell
Ans. (c) It can be the site of energy generation
Explanation: Energy generation is the function of mitochondria.
6. Following are a few definitions of osmosis
Read carefully and select the correct definition
(a) Movement of water molecules from a region of higher concentration to a region of
lower concentration through a semipermeable membrane
(b) Movement of solvent molecules from its higher concentration to lower concentration
(c) Movement of solvent molecules from higher concentration to lower concentration of solution through a permeable membrane
(d) Movement of solute molecules from lower concentration to higher concentration of solution through a semipermeable membrane
Ans. (a) Movement of water molecules from a region of higher concentration to a region of lower concentration through a semipermeable membrane
7. Plasmolysis in a plant cell is defined as
(a) break down (lysis) of plasma membrane in hypotonic medium
(b) shrinkage of cytoplasm in hypertonic medium
(c) shrinkage of nucleoplasm
(d) none of them
Ans. (b) shrinkage of cytoplasm in hypertonic medium
Explanation: When a cell is kept in hypertonic solution, it results in exosmosis. Most of the fluid goes out of the cell; resulting in shrinkage of cytoplasm.
8. Which of the following are covered by a single membrane?
(a) Mitochondria
(b) Vacuole
(c) Lysosome
(d) Plastid
Ans. (b) Vacuole
Explanation: Other organelles in the options are double – membrane structures.
9. Find out the false sentences
(a) Golgi apparatus is involved with the formation of lysosomes
(b) Nucleus, mitochondria and plastid have DNA; hence they are able to make their own structural proteins
(c) Mitochondria is said to be the power house of the cell as ATP is generated in them.
(d) Cytoplasm is called as protoplasm
Ans. (a) Golgi apparatus is involved with the formation of lysosomes
Explanation: Golgi apparatus is involved in synthesis and storage of certain
biomolecules and has no role to play in the formation of lysosomes.
10. Find out the correct sentence
(a) Enzymes packed in Lysosomes are made through RER (rough endoplasmic reticulum)
(b) Rough endoplasmic reticulum and smooth endoplasmic reticulum produce lipid and protein respectively
(c) Endoplasmic reticulum is related with the destruction of plasma membrane
(d) Nucleoid is present inside the nucleoplasm of eukaryotic nucleus
Ans. (a) Enzymes packed in Lysosomes are made through RER (rough endoplasmic reticulum)
Explanation: RES has ribosomes on the surface and ribosomes are responsible for protein synthesis and thus for enzymes synthesis as well. Hence, option ‘a’ is correct and option ‘b’ is incorrect. ER has no role to play in destruction of plasma membrane. The undefined nuclear region in prokaryotes is called nucleoid.
11. Which cell organelle plays a crucial role in detoxifying many poisons and drugs in a cell?
(a) Golgi apparatus
(b) Lysosomes
(c) Smooth endoplasmic reticulum
(d) Vacuoles
Ans. (c) Smooth endoplasmic reticulum
Explanation: In the river cells of vertebrate, SER plays an important role in detoxifying many poisons and drugs.
12. The proteins and lipids, essential for building the cell membrane, are manufactured by
(a) rough endoplasmic reticulum
(b) golgi apparatus
(c) plasma membrane
(d) mitochondria
Ans. (a) rough endoplasmic reticulum
Explanation: Endoplasmic reticulum synthesise both lipids and proteins. However, RER mainly synthesise proteins and SER mainly synthesise lipids.
13. The undefined nuclear region of prokaryotes are also known as
(a) nucleus
(b) nucleolus
(c) nucleic acid
(d) nucleoid
Ans. (d) nucleoid
14. The cell organelle involved in forming complex sugars from simple sugars are
(a) endoplasmic reticulum
(b) ribosomes
(c) plastids
(d) golgi apparatus
Ans. (d) golgi apparatus
Explanation: Golgi apparatus is involved in repackaging of many biomolecules.
15. Which out of the following is not a function of vacuole?
(a) Storage
(b) Providing turgidity and rigidity to the cell
(c) Waste excretion
(d) Locomotion
Ans. (d) Locomotion
Explanation: Locomotion is carried out by specialized structures which are outside the cell but vacuoles are inside the cell.
