AP Biology photosynthesis test AP answers

The energy required to run the Calvin cycle reactions of photosynthesis comes from which two substances produced during the light-dependent reactions?

A. ATP and NADPH

Enzymes with their highest activity at an alkaline (basic) pH are represented by which of the following graphs?

A. Graph I only

Based on Figure 1, the net number of ATP molecules produced during glycolysis from the metabolism of a single glucose molecule is closest to which of the following?

B. 2

The carbon 'that makes up organic molecules in plants is derived directly from

B. Carbon fixed in photosynthesis

Which of the following is the best explanation for the pattern of change in mass of the organisms over time?

B. Cellular respiration

Which of the following describes a metabolic consequence of a shortage of oxygen in muscle cells?

C. A buildup of lactic acid in the muscle tissue due to fermentation.

In an experiment, a scientist isolates mitochondria from living cells and suspends them in 2 different buffered solutions... the results do the experiment can be used as evidence in support of which of the following scientific claims about mitochondrial activity?

C. ATP production in mitochondria requires a hydrogen ion gradient that favors movement of protons into the mitochondrial matrix

ATP serves as a common energy source for organisms because

C. Its energy can be easily transferred to do cellular work

If NaF is added to cells undergoing cellular respiration, which of the following will most likely accumulate in the cells?

D. 2-phosphoglycerate

Within the cell, many chemical reactions that, by themselves, require energy input (have a positive free-energy change) can occur because the reactions

A. May be coupled to the hydrolysis of ATP

During aerobic cellular respiration, oxygen gas is consumed at the same rate as carbon dioxide gas is produced. In order to provide accurate volumetric measurements of oxygen gas consumption, the experimental setup should include which of the following?

A. A substance that removes carbon dioxide gas

Which of the following statements about mitochondrial chemiosmosis is NOT true?

E. Heat energy is required to establish the electron transport chain.

Which of the following is an important difference between light-dependent and light-independent reactions of photosynthesis?

E. The light-dependent reactions produce ATP and NADPH; the light-independent reactions use energy stored in ATP and NADPH.

The reactions of glycolysis occur in the

A. Cytosol

The O2 released during photosynthesis comes from

B. H2O

Which of the following was the dependent variable in the researcher's experiment?

B. pH

A researcher claims that the synthesis of ATP from ADP and inorganic phosphate (Pi) is essential to cellular function. Which of the following statements best helps justify the researcher's claim?

D. ATP synthase is a mitochondrial enzyme that catalyze the conversion of ADP and Pi to ATP.

A researcher claims that increased atmospheric carbon dioxide levels cause increased growth rates in plants. Which of the following statements best supports the researcher's claim?

D. Atmospheric carbon dioxide is the raw material for photosynthesis, which plants rely on for producing sugars and other organic compounds.

The rate of oxygen production equaled the rate of oxygen consumption during which of the following time periods?

D. J to K

An increase in the rate of oxygen production by algae would be accompanied by a comparable increase in the rate of production of which of the following substances?

A. C6H12O6

Oxygen consumption can be used as a measure of metabolic rate because oxygen is

A. Necessary for ATP synthesis by oxidative phosphorylation

Which of the following best describes the role of water in photosynthesis?

B. Water molecules donate electrons to the electron transport chain

Scientists investigated the effect of oxygen levels on the net rate of carbon fixation in two types of plants. The plants were grown in either well-watered soil (control) or dry soil and then exposed to either 21% or 1% O2. The net rate of CO2 fixation for both types of plants was measured. Data are shown in figure 1 and figure 2. Which of the following statements about the rate of CO2 fixation in the two types of plants is supported by the data shown in the figures?

A. At 21% O2, plant type 2 has a lower rate of CO2 fixation than plant type 1 does in both types of soil.

The figure can best assist in answering which of the following questions?

A. Do electron transport chains create a gradient so that ATP synthase can generate ATP molecules?

A researcher claims that only a portion of the light energy captured by green plants is available for growth and repair. Which of the following observations best helps justify the researcher's claim?

A. Light-capturing pigment molecules in green plants absorb red, blue, and violet light but reflect green light.

Two nutrient solutions are maintained at the same pH. Actively respiring mitochondria are isolated and placed into each of the two solutions. Oxygen gas is bubbled into one solution. The other solution is depleted of available oxygen. Which of the following best explains why ATP production is greater in the tube with oxygen than in the tube without oxygen?

A. The rate of proton pumping across the inner mitochondrial membrane is lower in the sample without oxygen

If the input water is labeled with a radioactive isotope of oxygen, O, then the oxygen gas released as the reaction proceeds is also labeled with O. Which of the following is the most likely explanation?

B. During the light reactions of photosynthesis, water is split, removing electrons and protons, and oxygen gas is released.

Which metabolic process is common to both aerobic cellular respiration and alcoholic fermentation?

B. Glycolysis

Which of the following question is most relevant to understanding the Calvin cycle?

B. How is ATP used in the formation of 3-carbon carbohydrates?

Which of the following questions will best direct an investigation of the mechanism of ATP synthase?

B. Is the phosphorylation of ADP by ATP synthase dependent on the formation of a proton gradient?

Based on the data shown, changes in the light intensity resulted in changes in the rate of which of the following processes?

B. Photosynthesis

During respiration, most ATP is formed as a direct result of the net movement of

B. Protons down a concentration gradient

Figure 1. Diagram of the electron transport chain and ATP synthase in the membrane of mitochondria. On average, more ATP can be produced from the NADH molecule than can be produced from a molecule of FADH2. Based on Figure 1, which of the following best explains the difference in ATP production between these two molecules?

B. The electrons of FADH2 are transferred through three complexes of the electron transport chain whereas those of NADH are transferred through all four complexes.

The figure above shows an organelle typically found in eukaryotic cells. Which of the following best describes the function of the double membrane system of this organelle?

B. The inner membrane has specialized proteins that create a hydrogen ion concentration gradient between the inter membrane space and the matrix

Newborn babies and hibernating animals contain a large amount of brown adipose (fat) tissue (BAT). Certain proteins in the BAT cells increase the permeability of the inner mitochondrial membrane to protons, disrupting the proton gradient. Which of the following best predicts the effect of disrupting the proton gradient in BAT?

C. Electron transport and oxidative phosphorylation will be decoupled, generating more heat but less ATP.

According to the chemiosmotic theory (chemiosmotic coupling), the energy required to move protons from the mitochondrial matrix to the intermembrane space against a concentration gradient comes most directly from...

D. Electrons flowing along the electron transport chain

What most likely causes the trends in oxygen concentrations shown in the graph above?

D. Photosynthesis produces more oxygen than is consumed by respiration during the day?

Which of the following best describes the function of the coenzymes NAD+ and FAD in eukaryotic cellular respiration?

E. They accept electrons during oxidation-reduction reactions