biology MCQs - 11th class Chapter 11 Mcqs

1

Bioenergetics is the quantitative study of energy relationships and energy conversions in ______.

A

chemical systems

B

physical systems

C

biological systems

D

mechanical systems

2

Biological energy transformations obey the laws of ______.

A

thermodynamics

B

motion

C

gravity

D

magnetism

3

All life on this planet Earth is powered, directly or indirectly, by ______.

A

geothermal energy

B

solar energy

C

wind energy

D

nuclear energy

4

The chloroplasts of plants capture light energy and convert it into ______.

A

kinetic energy

B

potential energy

C

electrical energy

D

chemical energy

5

The presence of free oxygen in the atmosphere made possible the evolution of ______.

A

photosynthesis

B

respiration

C

fermentation

D

glycolysis

6

What process releases a great deal of energy and couples it to the formation of ATP?

A

Photosynthesis

B

Glycolysis

C

Respiration

D

Fermentation

7

ATP is a kind of chemical link between ______ and anabolism.

A

catabolism

B

metabolism

C

hydrolysis

D

synthesis

8

Photosynthesis is an energy-capturing process, while ______ is an energy-releasing process.

A

glycolysis

B

respiration

C

Calvin cycle

D

chemiosmosis

9

In photosynthesis, energy-poor inorganic compounds are reduced to energy-rich ______.

A

proteins

B

lipids

C

carbohydrate

D

nucleic acids

10

In the simplified summary equation of photosynthesis, what are the reactants besides light energy?

A

C6H12O6 and 6O2

B

6CO2 and 6H2O

C

6CO2 and C6H12O6

D

6O2 and 6H2O

11

At the compensation point, the rate of photosynthesis is ______ the rate of respiration.

A

greater than

B

less than

C

equal to

D

unrelated to

12

According to Van Niel's hypothesis, the oxygen released during photosynthesis comes from ______.

A

carbon dioxide

B

glucose

C

water

D

chlorophyll

13

The hydrogen produced by the splitting of water reduces NADP to ______.

A

NADPH2

B

FADH2

C

ATP

D

ADP

14

Which part of the plant is considered the major site of photosynthesis?

A

Roots

B

Stems

C

Flowers

D

Leaves

15

The dense fluid-filled region in a chloroplast is called the ______.

A

granum

B

thylakoid

C

stroma

D

lumen

16

In chloroplasts, the light reactions take place on the ______.

A

stroma

B

grana

C

outer membrane

D

inner membrane

17

Photosynthetic pigments are found embedded in the ______ membranes.

A

stroma

B

nuclear

C

thylakoid

D

mitochondrial

18

What are the substances that absorb visible light (380-750 nm in wavelength)?

A

Enzymes

B

Hormones

C

Pigments

D

Lipids

19

Which instrument is used to measure the relative abilities of different pigments to absorb different wavelengths of light?

A

Microscope

B

Telescope

C

Spectrophotometer

D

Centrifuge

20

Besides chlorophylls, what other accessory pigments are present in chloroplasts?

A

Anthocyanins

B

Flavonoids

C

Carotenoids

D

Betalains

21

Which atom is present in the center of the porphyrin ring of a chlorophyll molecule?

A

Iron

B

Magnesium

C

Manganese

D

Copper

22

The long hydrocarbon tail of a chlorophyll molecule is called ______.

A

phytol

B

glycerol

C

stearate

D

palmitate

23

What is the only structural difference between chlorophyll a and chlorophyll b?

A

A methyl group vs a carbonyl group

B

A hydrocarbon tail vs a head

C

A phytol tail vs a porphyrin ring

D

A magnesium atom vs an iron atom

24

Which chlorophyll is the most abundant and directly participates in light-dependent reactions?

A

Chlorophyll b

B

Chlorophyll c

C

Chlorophyll a

D

Chlorophyll d

25

Carotenoids and chlorophyll b are called accessory pigments because they transfer absorbed energy to ______.

A

chlorophyll a

B

ATP

C

NADPH

D

water

26

Light behaves as waves and as particles called ______.

A

electrons

B

protons

C

neutrons

D

photons

27

The first action spectrum of photosynthesis was obtained by T.W. Engelmann in 1883 using ______.

A

Spirogyra

B

Chlamydomonas

C

Volvox

D

Euglena

28

In the Calvin cycle, CO2 is fixed by reacting with which five-carbon sugar?

A

Ribulose bisphosphate (RuBP)

B

Fructose-6-phosphate

C

Glyceraldehyde 3-phosphate (G3P)

D

Ribose-5-phosphate

29

The enzyme that catalyzes the reaction between CO2 and RuBP is called ______.

A

hexokinase

B

rubisco

C

ATP synthase

D

pepsin

30

The initial product of carbon fixation in the Calvin cycle is an unstable six-carbon intermediate that breaks into two molecules of ______.

A

3-phosphoglycerate (PGA)

B

glyceraldehyde 3-phosphate (G3P)

C

1,3-bisphosphoglycerate

D

ribulose bisphosphate (RuBP)

31

During the reduction phase of the Calvin cycle, PGA is converted to ______.

A

G3P

B

RuBP

C

Fructose

D

Glucose

32

For every three molecules of CO2 that enter the Calvin cycle, how many molecules of G3P are formed?

A

One

B

Three

C

Six

D

Nine

33

Out of every six molecules of G3P formed, how many leave the cycle as a net gain?

A

One

B

Three

C

Five

D

Six

34

The regeneration of RuBP from G3P requires the energy from ______.

A

ATP

B

NADPH

C

FADH2

D

GTP

35

The universal process by which organisms break down complex carbon compounds to harvest energy is called ______.

A

photosynthesis

B

respiration

C

digestion

D

transpiration

36

The splitting of glucose into two molecules of pyruvic acid is known as ______.

A

Krebs cycle

B

electron transport chain

C

glycolysis

D

fermentation

37

In the absence of oxygen, pyruvic acid can be broken down by ______.

A

aerobic respiration

B

Krebs cycle

C

alcoholic fermentation

D

oxidative phosphorylation

38

In muscle cells during extreme physical activities, pyruvic acid is converted into ______.

A

ethyl alcohol

B

lactic acid

C

acetic acid

D

citric acid

39

The 'powerhouses' of the cell that produce energy for cellular functions are the ______.

A

nuclei

B

ribosomes

C

chloroplasts

D

mitochondria

40

The breaking of the terminal phosphate bond of ATP releases about ______ Kcal of energy.

A

2.3

B

5.3

C

7.3

D

9.3

41

Glycolysis occurs in the ______ of the cell.

A

mitochondrion

B

nucleus

C

cytosol

D

chloroplast

42

During the preparatory phase of glycolysis, glucose is converted into ______.

A

pyruvic acid

B

fructose 1,6-bisphosphate

C

acetyl CoA

D

citrate

43

The end product of glycolysis is ______.

A

glucose

B

acetyl CoA

C

pyruvic acid

D

citric acid

44

Before entering the Krebs cycle, pyruvic acid is converted into ______.

A

citrate

B

oxaloacetate

C

acetyl CoA

D

succinate

45

The Krebs cycle begins with the union of acetyl CoA and ______ to form citrate.

A

succinate

B

malate

C

fumarate

D

oxaloacetate

46

In the Krebs cycle, which molecule is the oxidizing agent for the conversion of succinate to fumarate?

A

NAD

B

FAD

C

ATP

D

CoA

47

Synthesis of ATP in the presence of oxygen is called ______.

A

photophosphorylation

B

substrate-level phosphorylation

C

oxidative phosphorylation

D

chemiosmosis

48

In the respiratory chain, the final acceptor of electrons is ______.

A

NAD+

B

FAD

C

cytochrome c

D

oxygen

49

The mechanism for ATP synthesis in both photosynthesis and respiration is ______.

A

glycolysis

B

fermentation

C

Krebs cycle

D

chemiosmosis