Explore topic-wise MCQs in Life Sciences.

This section includes 134 Mcqs, each offering curated multiple-choice questions to sharpen your Life Sciences knowledge and support exam preparation. Choose a topic below to get started.

1.

What is reduction potential?

A. The molecule loses an electron
B. An atom/molecule gains an electron
C. Reducing the power of an electron
D. Oxidation power of an electron
Answer» C. Reducing the power of an electron
2.

What is the name of the molecule which donates its electrons?

A. Reducing agent
B. Oxidative agent
C. Standard reduction potential
D. Oxidant
Answer» B. Oxidative agent
3.

Which of the following equation gives the relationship between ∆G֯ and Keq?

A. ∆G֯ = -RT ln Keq
B. ∆G֯ = ln Keq
C. ∆G = ∆G֯ (-RT Keq)
D. ∆G = -RT ln Keq
Answer» B. ∆G֯ = ln Keq
4.

Which of the following factor is not responsible for the actual change in free energy (∆G)?

A. Temperature
B. Pressure
C. The initial concentration of reactant and products
D. pH
Answer» E.
5.

What is the value of ∆G, when a system is in equilibrium?

A. ∆G = 0
B. ∆G = 1
C. ∆G = -1
D. ∆G = ∆G֯
Answer» B. ∆G = 1
6.

Which of the following equation shows the relationship between free energy change (∆G) and the change in entropy (∆S), under constant temperature and pressure?

A. ∆G = T∆H – ∆S
B. ∆G = T∆H/∆S
C. ∆G = ∆H/T∆S
D. ∆G = ∆H – T∆S
Answer» E.
7.

Gibb’s free energy is the portion of the total energy which is available for useful work.

A. True
B. False
Answer» B. False
8.

What is the process of synthesis of glucose by the liver is referred to as?

A. gluconeogenesis
B. neogenesis
C. glycolysis
D. saccharification
Answer» B. neogenesis
9.

Feedback inhibition is cell’s mechanism to _____________ the process of anabolism.

A. activate
B. inhibit
C. increase
D. decrease
Answer» C. increase
10.

Allosteric site is same as enzyme’s active site.

A. True
B. False
Answer» C.
11.

Induced fit in an enzyme refers to ____________________

A. error
B. loop
C. conformational change
D. torsional change
Answer» D. torsional change
12.

Chymotrypsin is a ___________

A. starch
B. polymer
C. buffer
D. enzyme
Answer» E.
13.

What will happen if heat is applied to an enzyme mediated reaction?

A. Rate will increase
B. pH will increase
C. pH will decrease
D. Denaturation of enzyme
Answer» B. pH will increase
14.

Enzymes have no effect on which of the following, in a chemical reaction?

A. activation energy
B. speed
C. thermodynamics
D. completion time
Answer» D. completion time
15.

The non-protein constituents of conjugated proteins are called ___________

A. enzymes
B. cofactors
C. amino acids
D. nucleosides
Answer» C. amino acids
16.

Protein catalysts are called __________ and RNA catalysts are called _____________

A. enzymes, ribozymes
B. ribozymes, enzymes
C. enzymes, ribosomes
D. ribosomes, enzymes
Answer» B. ribozymes, enzymes
17.

Which of the following are responsible virtually for every reaction that takes place inside a cell?

A. Carbohydrates
B. ADP
C. Nucleic acids
D. Enzymes
Answer» B. ADP
18.

Cellular metabolism is a non-equilibrium metabolism.

A. True
B. False
Answer» B. False
19.

Hydrolysis of ATP is which type of reaction?

A. Physical
B. Mechanical
C. Endergonic
D. Exergonic
Answer» E.
20.

Exergonic processes are thermodynamically unfavorable.

A. True
B. False
Answer» C.
21.

According to laws of thermodynamics, the energy of the Universe is _________ whereas the entropy ______________

A. constant, increases
B. constant, decreases
C. increases, remains constant
D. decreases, remains constant
Answer» B. constant, decreases
22.

Reactions that lose heat are termed as _____________

A. endothermic
B. exothermic
C. chemical
D. physical
Answer» C. chemical
23.

Inorganic gases released during decomposition includes

A. carbon dioxide
B. hydrogen sulphide
C. water vapors
D. all of above
Answer» E.
24.

Alternative path adopted by photo excited electrons is

A. cyclic electron flow
B. non-cyclic electron flow
C. cyclic neutron flow
D. non-cyclic proton flow
Answer» B. non-cyclic electron flow
25.

Oxygen which is released during process of photosynthesis comes from

A. hydrogen
B. leaves
C. water
D. oxygen
Answer» D. oxygen
26.

Tail attached to pyrrole ring is called

A. porpyrin
B. tail
C. phytol
D. nostale
Answer» D. nostale
27.

Light is form of energy called

A. electromagnetic energy
B. radiations
C. longitudinal-wave patterned energy
D. Both a and b
Answer» E.
28.

Yellowing of plants is due to absence of

A. calcium
B. chlorophyll
C. magnesium
D. nitrogen
Answer» D. nitrogen
29.

Inorganic salts released during decomposition include

A. nitrate
B. sulfate
C. phosphate
D. all of above
Answer» E.
30.

Splitting of water molecule releasing oxygen is called

A. photosynthesis
B. photolysis
C. photolytic
D. photophosphorylation
Answer» C. photolytic
31.

Second pay off phase of cellular respiration is called

A. preparatory phase
B. net phase
C. respiratory phase
D. oxidative phase
Answer» E.
32.

Type of respiration which humans adopt in severe physical activities is

A. aerobic
B. anaerobic
C. fermentation
D. accumulation
Answer» C. fermentation
33.

Most abundant and most important photosynthetic pigment is

A. chlorophyll-a
B. chlorophyll-b
C. chlorophyll-c
D. chlorophyll-d
Answer» B. chlorophyll-b
34.

Fungi paly a role as decomposers through enzyme

A. protease
B. lactase
C. ADH
D. insulin
Answer» B. lactase
35.

Link between composers and decomposers is called as

A. nitrogen cycle
B. water cycle
C. carbon cycle
D. fertility restoration process
Answer» D. fertility restoration process
36.

Exchange of gases between organism and environment is termed as

A. internal respiration
B. external respiration
C. respiration
D. acquired respiration
Answer» C. respiration
37.

Phases of Calvin cycle involves

A. carbon fixation
B. reduction
C. regeneration
D. All of the Above
Answer» E.
38.

Synthesis of ATP by initiation of reaction with light is called

A. photophosphorylation
B. photolysis
C. photo system
D. photosynthesis
Answer» B. photolysis
39.

End product of glycolsis is

A. glucose
B. pyruvic acid
C. citric acid
D. glycogen
Answer» C. citric acid
40.

Reactions which are light-independent are termed as

A. light reactions
B. dark reactions
C. gaseous reactions
D. dull reactions
Answer» C. gaseous reactions
41.

Dense fluid filled region which helps in producing carbohydrate molecules is called

A. lumen
B. carpel
C. stroma
D. grana
Answer» D. grana
42.

Special complex which is build in thylakoid membrane which helps in moving down gradient is called

A. ATP complex
B. ATP synthetase
C. ATP synthase
D. ANP complex
Answer» D. ANP complex
43.

Oxidizing agent which removes hydrogen from fumarate is called

A. FAD
B. NAD
C. NADP
D. NADPH
Answer» B. NAD
44.

T.W.Engleman, in 1833, obtained first action spectrum while working on

A. bacteria
B. virus
C. spirogyra
D. fungi
Answer» D. fungi
45.

Smallest particles of light are called

A. dust
B. protons
C. photons
D. positrons
Answer» D. positrons
46.

Wave-length of a visible light ranges between

A. 360-678
B. 380-750
C. 280-670
D. 380-700`
Answer» C. 280-670
47.

Molecule of chlorophyll is composed of

A. hydrophyllic head
B. tail
C. Both a and b
D. hydrophillc joint
Answer» D. hydrophillc joint
48.

Biogas includes none ,but

A. carbon monoxide
B. carboxyl acids
C. methane
D. ethane
Answer» D. ethane
49.

During dark reactions, photosynthesis takes place by help of certain enzymes through cycle called

A. kerb's cycle
B. life cycle
C. calvin cycle
D. nitrogen cycle
Answer» D. nitrogen cycle
50.

There is a chemical link between anabolism and catabolism in form of

A. ADP
B. ATP
C. ATT
D. ASP
Answer» C. ATT