Exam 8: Photosynthesis: Using Sunlight to Build Carbohydrates

In photosynthesis, the electrons from _____ are used to reduce _____.

Which of the following sequences CORRECTLY represents the flow of energy through living systems?

Which molecule is oxidized in the photosynthetic reaction?

The reactions of the Calvin cycle used to be referred to as the "dark reactions" of photosynthesis, implying that light was not required for this pathway to incorporate CO₂ into carbohydrate. However, in the absence of light the Calvin cycle shuts down. Which step of the Calvin cycle would be impacted FIRST by the absence of light energy?

Normally, most xanthophylls present in the thylakoid membrane are associated with photosystem II. If a mutation occurred that caused xanthophylls to be randomly distributed in the thylakoid membrane, what would you predict would happen?

In the light-dependent reactions of photosynthesis, light energy is captured and stored as potential energy. In which of the following is this energy stored in the light-dependent reactions?

Carbon enters the Calvin cycle in the form of:

A new experimental pesticide is being tested by a large agricultural chemical company. An unfortunate side effect in plants treated with this new product is a decrease in NADPH production in the chloroplasts. (Interestingly, reduction of NAD⁺ to NADH in the mitochondria is unaffected.) Given this observation, what specific change(s), if any, would you expect to observe in the amounts of ATP, 3-phosphoglycerate and glyceraldehyde-3-phosphate, and RuBP in the chloroplasts of these plants?

The pH in the stroma of the chloroplast should be _____ compared with the thylakoid lumen due to the _____ concentration of protons in the thylakoid lumen.

A new experimental pesticide is being tested by a large agricultural chemical company. An unfortunate side effect in plants treated with this new product is a decrease in ATP production in the chloroplasts. (Interestingly, production of ATP in the mitochondria is unaffected.) Given this observation, which of the following would you expect to be DIRECTLY affected by the new pesticide?

In the Calvin cycle, ATP is required to:

The enzyme called rubisco:

Animal cells have mitochondria but no chloroplasts, while plant cells have chloroplasts but no mitochondria.

Photosystem I is a _____ than photosystem II.

Protons in a chloroplast flow through an ATP synthase from the:

The organisms believed to be the first to use two different photosystems in a single photosynthetic electron transport chain are the:

In the chloroplast, cytochrome b₆f is an important complex in the photosynthetic electron transport chain because it accepts electrons from photosystem II and donates them to photosystem I. Explain why the repeated reduction and oxidation of cytochrome b₆f is a vital step in the light dependent reactions and why it is critical to the overall process of photosynthesis.

In the chloroplast, cytochrome b₆f is an important complex in the photosynthetic electron transport chain because it accepts electrons from photosystem II and donates them to photosystem I. Another vital function of cytochrome b₆f is that, during its reduction-oxidation cycle, it moves _____ from the _____.

The oxidation of pyruvate occurs in the:

Leaves absorb the LEAST amount of light in the _____ range of the visible spectrum.