Photosynthesis AP Biology

If the proton (H+) pump in the thylakoid was not working, which molecule could not be made during the light reaction?

• NADPH

• ATP

• Water

• Oxygen gas

Answer explanation

If the proton pump in the thylakoid is not functioning, ATP cannot be produced during the light reaction.

Which statement about the Calvin cycle is FALSE?

• It uses the products of light reactions.

• It produces a three-carbon sugar (G3P).

• It produces carbon dioxide.

• It produces NADP+.

Answer explanation

The statement 'It produces carbon dioxide' is false because the Calvin cycle actually consumes carbon dioxide to produce a three-carbon sugar (G3P).

Tags

NGSS.HS-LS2-5

Which of the following is the correct equation for photosynthesis?

• 6CO₂ + 6H₂O --> 6O₂ + C₆H₁₂O₆

• 6CO₂ + C₆H₁₂O₆ + 6H₂O --> O₂

• 6O₂ + 6H₂O --> 6CO₂ + C₆H₁₂O₆

• C₆H₁₂O₆ + 6O₂ --> 6H₂O + 6CO₂

Answer explanation

The correct equation for photosynthesis is 6CO2 + 6H2O --> 6O2 + C6H12O6. This equation represents the process by which plants convert carbon dioxide and water into oxygen and glucose through the use of sunlight.

Tags

NGSS.HS-LS1-5

NGSS.HS-LS2-5

Where does a plant absorb the water that it uses during photosynthesis?

• Leaves

• Stem

• Roots

• Petals

Answer explanation

Plants absorb water for photosynthesis through their roots.

Tags

NGSS.MS-LS1-6

Which of the following statements best represents the relationships between the light reactions and the Calvin cycle?

• The light reactions provide ATP and NADPH to the Calvin cycle, and the Calvin cycle returns ADP, Pi, and NADP+ to the light reactions.

• The light reactions provide ATP and NADPH to the carbon fixation step of the Calvin cycle, and the Calvin cycle provides water and electrons to the light reactions.

• The light reactions supply the Calvin cycle with CO2 to produce sugars, and the Calvin cycle supplies the light reactions with sugars to produce ATP.

• The light reactions provide the Calvin cycle with oxygen for carbon fixation, and the Calvin cycle provides the light reactions with sugars to produce ATP.

Answer explanation

The light reactions provide ATP and NADPH to the Calvin cycle, and the Calvin cycle returns ADP, Pi, and NADP+ to the light reactions.

A stack of thylakoids is called ________.

• Granum

• Stomata

• Stroma

• Chloroplast

Answer explanation

A stack of thylakoids is called Granum. Thylakoids are membrane-bound compartments in chloroplasts where photosynthesis takes place.

Is the process of building a carbohydrate in the Calvin Cycle endergonic or exergonic, and why?

• Endergonic because carbohydrate production is catabolic

• Exergonic because carbohydrate production is anabolic

• Endergonic because carbohydrate production is anabolic

• Exergonic because carbohydrate production is catabolic

Answer explanation

The process of building a carbohydrate in the Calvin Cycle is endergonic because carbohydrate production is anabolic.

Tags

NGSS.HS-LS2-3

What is the function of NADP+?

• It absorbs light

• It is an electron carrier

• It is a light-reflecting pigment

• It acts as long-term energy storage

Answer explanation

NADP+ functions as an electron carrier.

Which of the following molecules is not needed for the Calvin Cycle?

• CO₂

• ATP

• NADPH

• H₂O

Answer explanation

H2O is not needed for the Calvin Cycle because it is not directly involved in the carbon fixation process.

Tags

NGSS.HS-LS1-5

NGSS.HS-LS2-5

Green plants reflect which color of light?

• Red

• Green

• All

• Red and Violet

Answer explanation

Green plants reflect green light.