mastering bio 10

In the electromagnetic spectrum, the type of radiation that we call visible light occurs between _____.

ultraviolet radiation and infrared radiation

When light strikes chlorophyll molecules, they lose electrons, which are ultimately replaced by _____

splitting water

Photosynthesis is a redox reaction. This means that H2O is _____ during the light reactions and CO2 is _____ during the Calvin cycle.

oxidized…reduced

The overall function of the Calvin cycle is _____.

making sugar

C4 plants occur more commonly in desert conditions because _____.

they can fix carbon at the lower CO2 concentrations that develop when the stomata are closed

Plants are photoautotrophs. What does this mean?

They use light energy to drive the synthesis of organic molecules from inorganic materials

The ultimate source of energy to support most life on Earth is _____.

sunlight

Which of the following statements is a correct distinction between autotrophs and heterotrophs?
1. Only heterotrophs have mitochondria.
2. Autotrophs, but not heterotrophs, can nourish themselves beginning with and other nutrients that are inorganic.
3. Only heterotrophs require oxygen.
4. Only heterotrophs require chemical compounds from the environment.
5. Cellular respiration is unique to heterotrophs.

2

Which of the following does not occur during the Calvin cycle
1. consumption of ATP
2. carbon fixation
3. release of oxygen
4. regeneration of the acceptor
5. oxidation of NADPH

3

The photosynthetic membranes are found in the _____ in plant cells.

chloroplasts

Where does the Calvin cycle take place?

stroma of the cholorplast

Which of the following is a product of the light reactions of photosynthesis?
1 high-energy photons
2 water and CO2
3 glyceraldehyde-3-phosphate
4 NADP+ and RuBP
5 oxygen, ATP, and NADPH

5

Which of the following products of the light reactions of photosynthesis is consumed during the Calvin cycle?
1. sugar
2. NADPH
3. oxygen
4. ADP + Pi
5. water

2

Compared to C3 plants, C4 plants

can continue to fix CO2 even at relatively low CO2 concentrations and high oxygen concentrations.

CAM plants keep stomata closed in daytime, thus reducing loss of water. They can do this because they

fix CO2 into organic acids during the night

Which of these equations best summarizes photosynthesis?
1. 6 CO2 + 6 O2 → C6H12O6 + 6 H2O
2. H2O → 2 H+ + 1/2 O2 + 2e-
3. C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy
4. C6H12O6 + 6 O2 → 6 CO2 + 12 H2O
5. 6 CO2 + 6 H2O → C6H12O6 + 6 O2

5

Where does the Calvin cycle occur?

stroma

The light reactions of photosynthesis use _____ and produce _____.

water…NADPH

Which term describes ATP production resulting from the capture of light energy by chlorophyll?
1. Oxidative phosphorylation
2. Photophosphorylation
3. Dephosphorylation
4. Substrate-level phosphorylation

2

True or false? The chemiosmotic hypothesis states that the synthesis of ATP generates a proton gradient that leads to electron flow through an electron transport chain.

false

According to the chemiosmotic hypothesis, what provides the energy that directly drives ATP synthesis?

proton gradient

Which of the following particles can pass through the ATP synthase channel?
1. Protons
2. ATP
3. ADP
4. Inorganic phosphate

1

True or false? The region of ATP synthase that catalyzes the production of ATP from ADP and inorganic phosphate spans the chloroplast membrane.

false

Chloroplast membrane vesicles are equilibrated in a simple solution of pH 5. The solution is then adjusted to pH 8. Which of the following conclusions can be drawn from these experimental conditions?
1. ATP will be produced because the proton gradient favors proton movement through the ATP synthase channels.
2. ATP will not be produced because there is no ADP and inorganic phosphate in the solution.
3. The change in the solution’s pH results in a gradient across the chloroplast membranes such that there is a lower concentration of protons inside the vesicles and a higher concentration outside.
4. Protons will not diffuse toward the outside of the vesicles.

2

_____ has a longer wavelength than _____.

red…green

Which process produces oxygen?

photosynthesis

Which set of reactions uses H2O and produces O2?

the light-dependent reactions

What is the importance of the light-independent reactions in terms of carbon flow in the biosphere?

The light-independent reactions turn CO2, a gas, into usable carbon in the form of sugars.

True or false? The light-dependent reactions of photosynthesis use water and produce oxygen

true

Which of the following molecules is the primary product of photosystem I?
1. Oxygen
2. Carbon dioxide
3. NADPH
4. ATP

3

What is the biological significance of the light-independent reactions of photosynthesis?

They convert carbon dioxide to sugar.

Which of the following statements best describes the relationship between the light-dependent and light-independent reactions of photosynthesis?
1. The light-dependent reactions pass electrons through an electron transport chain to the light-independent reactions.
2. The light-dependent reactions produce carbon dioxide, which is then used by the light-independent reactions.
3. The light-independent reactions release energy, and the light-dependent reactions require energy.
4. The light-dependent reactions produce ATP and NADPH, which are then used by the light-independent reactions.

4

Which of the following reactions ensures that the Calvin cycle can make a continuous supply of glucose?
1. Regneration of RuBP
2. Production of 3-phosphoglycerate
3. Production of G3P
4. Carbon fixation

1

Carbon fixation involves the addition of carbon dioxide to _____.

RuBP

After 3-PGA is phosphorylated, it is reduced by _____.

NADPH

How many carbon dioxide molecules must be added to RuBP to make a single molecule of glucose?

6

In the Calvin cycle, how many ATP molecules are required to regenerate RuBP from five G3P molecules?

3