Question 1

Which of the following is/are rubisco substrates?

Accepted Answer

A) O2 
B) CO2 
C) RuBP 
D) CO2 and RuBP 
E) CO2, O2, and RuBP 
A) O2 
B) CO2 
C) RuBP 
D) CO2 and RuBP 
E) CO2, O2, and RuBP

Question 2

In the lab you isolate a chlorella mutant that is unable to switch xanthophyll pigments into the inactive, non-heat-dissipating form. If you released that mutant into a small pond shaded by trees, would the mutation spread, and why?

Accepted Answer

A) No, because the light absorbed by chlorophyll would be released as heat and thus not used to make ATP or NADPH. 
B) No, because the xanthophylls prevent the production of reactive oxygen species. 
C) Yes, because the xanthophylls prevent the production of reactive oxygen species. 
D) Yes, because the heat released by the xanthophylls would warm up the cells and enhance photosynthesis. 
E) No, because mutations never spread in nature. 
A) No, because the light absorbed by chlorophyll would be released as heat and thus not used to make ATP or NADPH. 
B) No, because the xanthophylls prevent the production of reactive oxygen species. 
C) Yes, because the xanthophylls prevent the production of reactive oxygen species. 
D) Yes, because the heat released by the xanthophylls would warm up the cells and enhance photosynthesis. 
E) No, because mutations never spread in nature.

Question 3

What is the MOST abundant protein on Earth?

Accepted Answer

A) rubisco 
B) CO2 
C) 3-PGA 
D) NADPH 
A) rubisco 
B) CO2 
C) 3-PGA 
D) NADPH

Question 4

Which one of the following statements BEST represents the relationship between cellular respiration and photosynthesis?

Accepted Answer

A) Respiration occurs only in animals and photosynthesis occurs only in plants. 
B) Photosynthesis occurs only in the day and respiration occurs only at night. 
C) Photosynthesis stores energy in organic molecules, while respiration releases it. 
D) Photosynthesis reverses the biochemical pathways of respiration. 
A) Respiration occurs only in animals and photosynthesis occurs only in plants. 
B) Photosynthesis occurs only in the day and respiration occurs only at night. 
C) Photosynthesis stores energy in organic molecules, while respiration releases it. 
D) Photosynthesis reverses the biochemical pathways of respiration.

Question 5

Which of the following is thought to be the FIRST group of organisms able to use water as an electron donor in photosynthesis?

Accepted Answer

A) land plants 
B) aquatic plants 
C) algae 
D) cyanobacteria 
A) land plants 
B) aquatic plants 
C) algae 
D) cyanobacteria

Question 6

For every six CO2 molecules incorporated into carbohydrate molecules, how many triose phosphates can be exported from the chloroplast?

Accepted Answer

A) 12 
B) 10 
C) 6 
D) 2 
E) 1 
A) 12 
B) 10 
C) 6 
D) 2 
E) 1

Question 7

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, which of the following would you NOT expect to observe in the chloroplasts of these plants?

Accepted Answer

A) a decrease in 3-phosphoglycerate levels and a decrease in RuBP production 
B) an increase in 3-phosphoglycerate levels and an increase in RuBP production 
C) a decrease in glyceraldehyde-3-phosphate production 
D) a decrease in 3-phosphoglycerate production and an increase in RuBP production 
A) a decrease in 3-phosphoglycerate levels and a decrease in RuBP production 
B) an increase in 3-phosphoglycerate levels and an increase in RuBP production 
C) a decrease in glyceraldehyde-3-phosphate production 
D) a decrease in 3-phosphoglycerate production and an increase in RuBP production

Question 8

The process in which one cell takes up residence in another cell is called:

Accepted Answer

A) commensalism. 
B) parasitism. 
C) endocytosis. 
D) exocytosis. 
E) endosymbiosis. 
A) commensalism. 
B) parasitism. 
C) endocytosis. 
D) exocytosis. 
E) endosymbiosis.

Question 9

Why is the absorption and capture of light energy by chlorophyll molecules in plants much more efficient than its absorption and capture by isolated chlorophyll molecules in the lab?

Accepted Answer

A) Because the plant produces accessory proteins. 
B) Because an artificial light source is used in the lab. 
C) Because in the plant, the energy is transferred to another chlorophyll. 
D) Because the lab has a higher e- supply. 
A) Because the plant produces accessory proteins. 
B) Because an artificial light source is used in the lab. 
C) Because in the plant, the energy is transferred to another chlorophyll. 
D) Because the lab has a higher e- supply.

Question 10

The reducing agent during the Calvin cycle is:

Accepted Answer

A) NADPH. 
B) ATP. 
C) oxygen. 
D) NADH. 
E) FADH2. 
A) NADPH. 
B) ATP. 
C) oxygen. 
D) NADH. 
E) FADH2.

Question 11

Recall that cyanobacteria may have developed as a result of transfer of genetic material: a bacterium carrying the genetic information for one photosystem received (from another bacterium) the genetic information for a second, distinct photosystem. What might be possible mechanisms of action for genetic transfer?

Accepted Answer

A) Bacteria could take up genetic information (released from dead bacteria)from their surroundings. 
B) Bacteria may exchange genetic information through the development of cytoplasmic connections. 
C) Bacteria may become infected by a virus that carries genetic information taken from previously infected bacteria. 
D) All of these choices are correct. 
A) Bacteria could take up genetic information (released from dead bacteria)from their surroundings. 
B) Bacteria may exchange genetic information through the development of cytoplasmic connections. 
C) Bacteria may become infected by a virus that carries genetic information taken from previously infected bacteria. 
D) All of these choices are correct.

Question 12

If a plant is exposed to a toxin that makes the thylakoid membranes permeable to protons, predict the impact of the toxin on each of the following the:
1. proton gradient across the thylakoid membrane.
2. oxidation of NADPH to NADP+.
3. pH in the thylakoid lumen.
4. production of carbohydrate in the Calvin cycle.

Accepted Answer

The proton gradient would dissipate; B:

Question 13

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

Accepted Answer

A) cytoplasm to the intermembrane space. 
B) intermembrane space to the cytoplasm. 
C) intermembrane space to the matrix. 
D) matrix to the intermembrane space. 
A) cytoplasm to the intermembrane space. 
B) intermembrane space to the cytoplasm. 
C) intermembrane space to the matrix. 
D) matrix to the intermembrane space.

Question 14

Assuming that all is working properly, which of the following is at a HIGHER energy level?

Accepted Answer

A) an excited-state reaction center chlorophyll 
B) an excited-state antenna chlorophyll 
A) an excited-state reaction center chlorophyll 
B) an excited-state antenna chlorophyll

Question 15

Which of the following statements is TRUE regarding the earliest photosynthetic organisms on Earth?

Accepted Answer

A) These organisms likely possessed two photosystems. 
B) Given the abundance of H2O on early Earth, these organisms used H2O as an electron donor. 
C) The organisms likely used molecules other than water (i.e., H2S)as electron donors. 
D) The organisms likely produced oxygen as a waste product, resulting in Earth's current atmosphere. 
E) These organisms likely used both inorganic molecules and water as electron donors. 
A) These organisms likely possessed two photosystems. 
B) Given the abundance of H2O on early Earth, these organisms used H2O as an electron donor. 
C) The organisms likely used molecules other than water (i.e., H2S)as electron donors. 
D) The organisms likely produced oxygen as a waste product, resulting in Earth's current atmosphere. 
E) These organisms likely used both inorganic molecules and water as electron donors.

Question 16

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, what reaction(s) of photosynthesis would you expect to be DIRECLTY affected by the new pesticide?

Accepted Answer

The synthesis of triose phosphates from

Question 17

The fluid-filled interior compartment of the thylakoid network is referred to as the:

Accepted Answer

A) stroma. 
B) grana. 
C) cytoplasm. 
D) lumen. 
E) intermembrane space. 
A) stroma. 
B) grana. 
C) cytoplasm. 
D) lumen. 
E) intermembrane space.

Question 18

Which of the following could be TRUE if a plant cell is exposed to a toxin that somehow causes the outer chloroplast membrane to be less permeable to water?

Accepted Answer

A) There would be a decrease in the amount of oxygen produced. 
B) The synthesis of ATP in the chloroplast would be unaffected. 
C) ATP generated by the mitochondria would be used to power photosynthesis, so plant cells would not have enough ATP left to supply the many other processes that require it. 
D) The cytoplasm of plant cells would become hypertonic. 
E) The amount of carbohydrate produced would increase. 
A) There would be a decrease in the amount of oxygen produced. 
B) The synthesis of ATP in the chloroplast would be unaffected. 
C) ATP generated by the mitochondria would be used to power photosynthesis, so plant cells would not have enough ATP left to supply the many other processes that require it. 
D) The cytoplasm of plant cells would become hypertonic. 
E) The amount of carbohydrate produced would increase.

Question 19

Explain why photosynthesis shuts down if the proton gradient present across the thylakoid membrane is NOT maintained.

Accepted Answer

When light is present, the electron tran

Question 20

The primary reason surplus carbohydrates in plants are stored as starch is because:

Accepted Answer

A) they would otherwise be utilized as energy sources even if such energy were not needed at that time. 
B) the space they occupy as carbohydrates is needed for other macromolecules. 
C) energy is needed in the nucleus, and only starch is capable of being transported into the nucleus. 
D) if they were left as individual monosaccharides, water would enter the cell by osmosis. 
E) All of these choices represent equally important reasons why surplus carbohydrates in plants are stored as starch. 
A) they would otherwise be utilized as energy sources even if such energy were not needed at that time. 
B) the space they occupy as carbohydrates is needed for other macromolecules. 
C) energy is needed in the nucleus, and only starch is capable of being transported into the nucleus. 
D) if they were left as individual monosaccharides, water would enter the cell by osmosis. 
E) All of these choices represent equally important reasons why surplus carbohydrates in plants are stored as starch.

Exam 8: Photosynthesis: Using Sunlight to Build Carbohydrates

Which of the following is/are rubisco substrates?

In the lab you isolate a chlorella mutant that is unable to switch xanthophyll pigments into the inactive, non-heat-dissipating form. If you released that mutant into a small pond shaded by trees, would the mutation spread, and why?

What is the MOST abundant protein on Earth?

Which one of the following statements BEST represents the relationship between cellular respiration and photosynthesis?

Which of the following is thought to be the FIRST group of organisms able to use water as an electron donor in photosynthesis?

For every six CO2 molecules incorporated into carbohydrate molecules, how many triose phosphates can be exported from the chloroplast?

The process in which one cell takes up residence in another cell is called:

Why is the absorption and capture of light energy by chlorophyll molecules in plants much more efficient than its absorption and capture by isolated chlorophyll molecules in the lab?

The reducing agent during the Calvin cycle is:

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

Assuming that all is working properly, which of the following is at a HIGHER energy level?

Which of the following statements is TRUE regarding the earliest photosynthetic organisms on Earth?

The fluid-filled interior compartment of the thylakoid network is referred to as the:

Which of the following could be TRUE if a plant cell is exposed to a toxin that somehow causes the outer chloroplast membrane to be less permeable to water?

Explain why photosynthesis shuts down if the proton gradient present across the thylakoid membrane is NOT maintained.

The primary reason surplus carbohydrates in plants are stored as starch is because:

Life: Chemical, Cellular, and Evolutionary Foundations

The Molecules of Life

Nucleic Acids and Transcription

Translation and Protein Structure

Organizing Principles: Lipids, Membranes, and Cell Compartments

Making Life Work: Capturing and Using Energy

Cellular Respiration: Harvesting Energy From Carbohydrates and Other Fuel Molecules

Cell Signaling

Cell and Tissue Architecture: Cytoskeleton, Cell Junctions, and Extracellular Matrix

Cell Division: Variations, Regulation, and Cancer

Dna Replication and Manipulation

Genomes

Mutation and Dna Repair

Genetic Variation

Mendelian Inheritance

Inheritance of Sex Chromosomes, Linked Genes, and Organelles

The Genetic and Environmental Basis of Complex Traits

Genetic and Epigenetic Regulation

Genes and Development

Evolution: How Genotypes and Phenotypes Change Over Time

Species and Speciation

Evolutionary Patterns: Phylogeny and Fossils

Human Origins and Evolution

Cycling Carbon

Bacteria and Archaea

Eukaryotic Cells: Origins and Diversity

Being Multicellular

Plant Structure and Function: Moving Photosynthesis Onto Land

Plant Reproduction: Finding Mates and Dispersing Young

Plant Growth and Development

Plant Defense: Keeping the World Green

Plant Diversity

Fungi: Structure, Function, and Diversity

Animal Nervous Systems

Animal Sensory Systems and Brain Function

Animal Movement: Muscles and Skeletons

Animal Endocrine Systems

Animal Cardiovascular and Respiratory Systems

Animal Metabolism, Nutrition, and Digestion

Animal Renal Systems: Water and Waste

Animal Reproduction and Development

Animal Immune Systems

Animal Diversity

Animal Behavior

Population Ecology

Species Interactions, Communities, and Ecosystems

Biomes and Global Ecology

The Anthropocene: Humans As a Planetary Force

Filters

For every six CO₂ molecules incorporated into carbohydrate molecules, how many triose phosphates can be exported from the chloroplast?