Question 1

Which of the following best explains why leaves appear green during the spring and summer months?

Accepted Answer

Chlorophyll a and b reflect green light, which is why leaves appear green.

Question 2

Which pigment is primarily responsible for absorbing blue and orange wavelengths of light in plants?

Accepted Answer

Chlorophyll b

Question 3

What is the main function of accessory pigments such as carotenoids in photosynthesis?

Accepted Answer

They absorb and dissipate excessive light energy that might damage chlorophyll.

Question 4

Beta-carotene, found in carrots and pumpkins, is important for human health because it is:

Accepted Answer

A precursor to vitamin A.

Question 5

Which structure within the chloroplast is the site where the light-dependent reactions of photosynthesis occur?

Accepted Answer

Thylakoid membrane

Question 6

During the light reactions of photosynthesis, what is the source of electrons for the electron transport chain?

Accepted Answer

Water ($$H_2O)$$

Question 7

Which of the following equations correctly summarizes the overall process of photosynthesis?

Accepted Answer

$$6CO_2 + 6H_2O + light \, energy \rightarrow C_6H_{12}O_6$ + 6O_2$$

Question 8

What is the primary role of NADPH in the Calvin cycle?

Accepted Answer

To donate electrons for the reduction of carbon compounds.

Question 9

Which enzyme catalyzes the fixation of carbon dioxide to RuBP in the Calvin cycle?

Accepted Answer

RuBisCo

Question 10

Why is the Calvin cycle considered a 'cycle'?

Accepted Answer

It regenerates its starting molecule, RuBP, allowing the process to continue.

Question 11

Which of the following best describes the relationship between photosynthesis and cellular respiration?

Accepted Answer

Photosynthesis uses the products of cellular respiration as its reactants.

Question 12

A mutation disables the water-splitting enzyme in Photosystem II. What would be the most immediate effect on the plant?

Accepted Answer

The plant would stop producing oxygen gas ($$O_2).$$

Question 13

Which of the following is a direct output of the Calvin cycle that can be used to synthesize glucose?

Accepted Answer

G3P (glyceraldehyde-3-phosphate)

Question 14

Which pigment is responsible for the red color in tomatoes and is being studied for its potential anti-cancer properties?

Accepted Answer

Lycopene

Question 15

What is the evolutionary significance of glycolysis being present in both aerobic respiration and fermentation?

Accepted Answer

It indicates glycolysis is a universal and ancient energy-harvesting process.

Question 16

Which of the following best describes the role of the electron transport chain (ETC) in the light reactions of photosynthesis?

Accepted Answer

It pumps $$H^+$$ ions across the thylakoid membrane, creating a gradient used to synthesize ATP.

Question 17

Which of the following is NOT a function of mitotic cell division in multicellular organisms?

Accepted Answer

Production of gametes

Question 18

What is the main reason why DNA must be tightly packed into chromosomes before cell division?

Accepted Answer

To ensure accurate and efficient distribution of genetic material to daughter cells.

Question 19

Which of the following statements about eukaryotic and prokaryotic DNA is correct?

Accepted Answer

Eukaryotic DNA is linear and found in the nucleus, while prokaryotic DNA is circular and found in the cytoplasm.

Question 20

A scientist observes a plant cell with a mutation that prevents the regeneration of RuBP. What would be the most likely consequence?

Accepted Answer

The Calvin cycle would stop, and glucose production would decrease.

Photosynthesis: Light Reactions, Pigments, and the Calvin Cycle

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