Photosynthesis: The Ultimate Guide to Plant Food Making

Question 1

In plant cells, the Calvin cycle occurs in which compartment?

Accepted Answer

Chloroplast stroma

Answer

Chloroplast thylakoids

Answer

Mitochondria

Answer

Cytoplasm

Question 2

Provide the balanced chemical equation that represents photosynthesis.

Accepted Answer

6CO2 + 6H2O + light energy → C6H12O6 + 6O2

Answer

C6H12O6 + 6O2 → 6CO2 + 6H2O + light energy

Answer

6CO2 + 12H2O → C6H12O6 + 6H2O

Answer

C6H12O6 + 6H2O → 6CO2 + 12H2O

Question 3

Identify the primary function of thylakoids in chloroplasts.

Accepted Answer

Contain the light-dependent reactions

Answer

Store starch

Answer

Transport electrons

Answer

Synthesize ATP

Question 4

Identify the primary purpose of cyclic photophosphorylation in the process of photosynthesis.

Accepted Answer

Generate ATP

Answer

Produce NADPH

Answer

Release oxygen

Answer

Fix carbon dioxide

Question 5

What is the primary role of photosynthesis in plants?

Accepted Answer

To generate chemical energy from light energy.

Answer

To produce oxygen as a byproduct.

Answer

To remove carbon dioxide from the atmosphere.

Answer

To synthesize proteins for plant growth.

Question 6

Which of the following is not a product of the light-dependent reactions of photosynthesis?

Accepted Answer

Glucose

Answer

ATP

Answer

NADPH

Answer

Oxygen

Question 7

Which of the following enzymes plays a crucial role in the Calvin cycle?

Accepted Answer

Rubisco

Answer

Cytochrome c oxidase

Answer

Hexokinase

Answer

Phosphofructokinase

Question 8

In which organelle does the Calvin cycle take place?

Accepted Answer

Chloroplasts

Answer

Mitochondria

Answer

Ribosomes

Answer

Vacuoles

Question 9

What is the primary photosynthetic pigment?

Accepted Answer

Chlorophyll a

Answer

Chlorophyll b

Answer

Carotenoids

Answer

Phycobilins

Question 10

What is the primary function of NADPH in photosynthesis?

Accepted Answer

Electron carrier

Answer

Energy currency

Answer

Carbon dioxide carrier

Answer

Oxygen carrier

Question 11

What process do plants use to convert light energy into chemical energy?

Accepted Answer

Photosynthesis

Answer

Respiration

Answer

Glycolysis

Answer

Krebs cycle

Question 12

What is the main function of the electron transport chain in photosynthesis?

Accepted Answer

Generate ATP through chemiosmosis

Answer

Pump protons across the thylakoid membrane

Answer

Reduce NADP+ to NADPH

Answer

Split water molecules

Question 13

What is the role of chlorophyll in the light-dependent reaction of photosynthesis?

Accepted Answer

Absorb light energy and transfer electrons

Answer

Produce oxygen

Answer

Split water molecules

Answer

Reduce NADP+ to NADPH

Question 14

Which substance is released as a by-product of the light-dependent reaction?

Accepted Answer

Oxygen

Answer

ATP

Answer

NADPH

Answer

Water

Question 15

What is the name of the enzyme that catalyses the fixation of carbon dioxide in the Calvin cycle?

Accepted Answer

Rubisco

Answer

Cytochrome oxidase

Answer

ATP synthase

Answer

NADH dehydrogenase

Question 16

Where do the light-independent reactions of photosynthesis occur?

Accepted Answer

Stroma

Answer

Chloroplast envelope

Answer

Thylakoid membranes

Answer

Mitochondria

Question 17

Which of the following is the main enzyme involved in the Calvin cycle?

Accepted Answer

Rubisco

Answer

ATP synthase

Answer

Cytochrome c oxidase

Answer

DNA polymerase

Question 18

What is the main role of chlorophyll in photosynthesis?

Accepted Answer

To absorb light energy

Answer

To transport electrons

Answer

To form ATP

Answer

To reduce CO₂

Question 19

How does oxygen enter the leaf during photosynthesis?

Accepted Answer

Stomata

Answer

Cuticle

Answer

Xylem vessels

Answer

Phloem vessels

Question 20

Which pigment is NOT involved in the light-dependent reactions of photosynthesis?

Accepted Answer

Phycobilins

Answer

Chlorophyll a

Answer

Chlorophyll b

Answer

Carotenoids

Question 21

During the Calvin cycle, which molecule is the primary product directly used to synthesize glucose?

Accepted Answer

Glyceraldehyde 3-phosphate (G3P)

Answer

Ribulose 1,5-bisphosphate (RuBP)

Answer

3-phosphoglycerate (3-PGA)

Answer

Fructose 1,6-bisphosphate (FBP)

Question 22

The energy currency used by plants for various cellular processes during photosynthesis is:

Accepted Answer

ATP and NADPH

Answer

Glucose and oxygen

Answer

Water and carbon dioxide

Answer

Chlorophyll and carotenoids

Question 23

The primary enzyme involved in the fixation of CO2 during photosynthesis is:

Accepted Answer

Rubisco

Answer

Cytochrome oxidase

Answer

ATP synthase

Answer

Nitrogenase

Question 24

Which of the following equations correctly represents the overall reaction of photosynthesis?

Accepted Answer

6CO2 + 6H2O + light energy → C6H12O6 + 6O2

Answer

6CO2 + 12H2O + light energy → C6H12O6 + 6H2O + 6O2

Answer

12CO2 + 12H2O + light energy → 2C6H12O6 + 6O2

Answer

6CO2 + 6H2O → C6H12O6 + 6O2 (in the absence of light)

Question 25

Photosystems are located on the:

Accepted Answer

Thylakoid membranes of chloroplasts

Answer

Inner mitochondrial membrane

Answer

Outer plasma membrane of cells

Answer

Nuclear envelope

Question 26

The process of converting light energy into chemical energy during photosynthesis takes place in the:

Accepted Answer

Thylakoids

Answer

Cytoplasm

Answer

Stroma

Answer

Mitochondria

Question 27

Which of the following pigments is NOT directly involved in the light-dependent reactions of photosynthesis?

Accepted Answer

Hemoglobin

Answer

Chlorophyll a

Answer

Chlorophyll b

Answer

Carotenoids

Question 28

In which part of the chloroplast do the light-dependent reactions of photosynthesis primarily occur?

Accepted Answer

Thylakoid membranes

Answer

Stroma

Answer

Cytoplasm

Answer

Mitochondria

Question 29

What is the primary carbohydrate product of the light-independent reactions of photosynthesis?

Accepted Answer

Glucose

Answer

ATP

Answer

Oxygen

Answer

NADPH

Question 30

Which of the following is NOT a reactant in the light-dependent reactions of photosynthesis?

Accepted Answer

Carbon dioxide

Answer

Light

Answer

Water

Question 31

In which organelle of plant cells does the Calvin cycle occur?

Accepted Answer

Stroma of chloroplasts

Answer

Thylakoids of chloroplasts

Answer

Mitochondria

Question 32

Which wavelengths of light are most effective for photosynthesis?

Accepted Answer

Blue and red

Answer

All wavelengths are equally effective

Answer

Orange and purple

Answer

Green and yellow

Question 33

What is the primary function of chlorophyll in photosynthesis?

Accepted Answer

To absorb light energy and convert it into chemical energy

Answer

To release oxygen as a byproduct

Answer

To transport electrons along the electron transport chain

Question 34

Which of the following is NOT a product of the light-dependent reactions?

Accepted Answer

Glucose

Answer

ATP

Answer

Oxygen

Answer

NADPH

Question 35

What is the primary role of the electron transport chain in photosynthesis?

Accepted Answer

To generate a proton gradient for ATP synthesis

Answer

To reduce NADP+ to NADPH

Answer

To fix carbon dioxide into glucose

Answer

To absorb light energy

Question 36

Which of the following is the major group of accessory pigments that broadens the spectrum of light absorbed for photosynthesis in plants?

Accepted Answer

Carotenoids

Answer

Chlorophyll a

Answer

Phycobilins

Answer

Chlorophyll b

Question 37

In which part of the chloroplast does the light-independent reaction of photosynthesis occur?

Accepted Answer

Stroma

Answer

Cytoplasm

Answer

Thylakoid membrane

Answer

Nucleus

Question 38

Which enzyme is pivotal in catalyzing the production of glucose during the Calvin cycle?

Accepted Answer

Rubisco

Answer

Polymerase

Answer

Chlorophyllase

Answer

Carboxylase

Question 39

What are the primary products of the light-dependent reactions of photosynthesis?

Accepted Answer

ATP and NADPH

Answer

Pyruvate

Answer

Acetyl-CoA

Answer

Glucose

Question 40

What is the main function of the Calvin cycle in photosynthesis?

Accepted Answer

Fixing carbon dioxide into glucose

Answer

Generating oxygen

Answer

Synthesizing chlorophyll

Answer

Pumping protons across the thylakoid membrane

Question 41

Which substance is NOT generated as a product of the Calvin cycle?

Accepted Answer

Ribulose-1,5-bisphosphate

Answer

Glyceraldehyde-3-phosphate

Answer

Glucose

Answer

Starch

Question 42

What are the main products of the light-dependent reactions in photosynthesis?

Accepted Answer

ATP and NADPH

Answer

Water

Answer

Oxygen

Answer

Glucose

Question 43

Which enzyme is responsible for fixing carbon dioxide during the Calvin cycle?

Accepted Answer

Rubisco

Answer

PEP carboxylase

Answer

ATP synthase

Question 44

Which factors can limit the rate of photosynthesis?

Accepted Answer

Light intensity, temperature, and water availability

Answer

Light intensity and temperature only

Answer

Temperature and water availability only

Question 45

Which wavelengths of light are most effectively used for photosynthesis?

Accepted Answer

Blue and red

Answer

Yellow and violet

Answer

Ultraviolet and infrared

Answer

Green and orange

Question 46

Where do the light-independent reactions of photosynthesis take place?

Accepted Answer

Stroma of the chloroplast

Answer

Thylakoid membrane of the chloroplast

Answer

Cytoplasm of the plant cell

Question 47

Which of the following is a product of the Calvin cycle?

Accepted Answer

Glucose

Answer

NADPH

Answer

Oxygen

Answer

ATP

Question 48

What is the primary importance of photosynthesis for life on Earth?

Accepted Answer

It provides the primary source of food and oxygen for living organisms.

Answer

It contributes to the formation of fossil fuels.

Answer

It regulates the Earth's atmosphere.