Chapter 7 Practice Quiz

Based on this graph, which wavelengths of light would result in the highest rates of ATP production during photosynthesis? 450-500 nanometers 550-600 nanometers 600-650 nanometers 700-750 nanometers

450-500 nanometers

The energy of the movement of electrons down a concentration gradient via electron transport within chloroplasts and mitochondria is used to generate ATP. glucose. O2. H2O. CO2.

ATP.

Enzymes are required during which of the following reactions? The Calvin cycle only The light reactions only Both the light reactions and the Calvin cycle Neither the light reactions nor the Calvin cycle

Both the light reactions and the Calvin cycle

Explain how the leaf is adapted for capturing energy from sunlight and for acquiring carbon dioxide and water.

CO2 comes through adjustable pores, or stomata, and water comes from the vascular bundles (or veins) to the mesophyll cells. Leaves are broad and flat to provide a large surface area to the sun. Chlorophyll molecules embedded in the thylakoid membrane of the chloroplast absorb sunlight.

Imagine that a scientist discovers a mutant plant seedling that appears to lack stomata. What would be the effect of this? Glucose would not be able to enter the plant as a reactant for photosynthesis. CO2 would not be able to enter the plant as a reactant for photosynthesis. Additional ATP would be produced by the seedling, and the plant would grow taller. Visible wavelengths of light would be unable to reach the chloroplasts.

CO2 would not be able to enter the plant as a reactant for photosynthesis.

What is the role of the green pigment chlorophyll in photosynthesis?

Chlorophyll is critical in light reactions to harness light energy and begin the flow of electrons, which in turn creates the proton gradient allowing for ATP formation, which is required for the Calvin cycle.

Consider the scenario of two scientists conducting an experiment to track what happens to the carbon atoms from CO2 molecules used during the Calvin cycle of photosynthesis. They add a radioactive "tag" to the carbon atoms of the CO2 reactants and then collect the products following the reactions. They analyze the products for their level of radioactivity. Which product(s) would you expect to be radioactive? Glucose only Both water and glucose Water only ATP only Both ATP and water

Glucose only

Based on the information provided in this figure, where does the oxygen gas produced by a leaf come from? C6H12O6 H2O CO2 NADPH

H2O

Which of the following is NOT true of chlorophyll? It absorbs light at the red and blue ends of the spectrum. It is found in the thylakoid membrane. It reflects green wavelengths of light. It is the main photosynthetic pigment in plants. It is found in mitochondria.

It is found in mitochondria.

Before photosynthesis evolved, ________ was rare in Earth's atmosphere. H2O CO2 N2 O2 air

O2

Suppose that you are experimenting with different types of lighting for your indoor green plants. Which of the following colors of light will be most effective? Green Black Orange and yellow Red and blue Red and green

Red and blue

What structural feature of a leaf enables it to obtain CO2 from the air? Epidermis Cuticle Mesophyll Chloroplast Stomata

Stomata

Give the simplest chemical equation for photosynthesis. For each reactant, indicate where the plant acquires it. For each product, note during what part of photosynthesis it is produced.

The chemical equation for photosynthesis is 6 CO2 + 6 H2O + light energy → C6H12O6 + 6 O2 CO2 comes through the stomata, water comes from the vascular bundles (or veins) to the mesophyll cells, and chlorophyll molecules embedded in the thylakoid membrane of the chloroplast absorb sunlight. The glucose is produced immediately following the Calvin cycle, and the oxygen is produced during the light reactions.

Based on the information provided in this figure, what event contributes directly to the creation of a proton gradient across the thylakoid membrane? The flow of electrons through electron transport chain II The creation of ATP The flow of electrons through photosystem I The creation of C6H12O6 The splitting of H2O

The flow of electrons through electron transport chain II

Pigments that absorb light energy to drive photosynthesis include carotenoids only. carotenoids and anthocyanins. anthocyanins only. chlorophyll only. chlorophyll and carotenoids.

chlorophyll and carotenoids.

You are carrying out an experiment on several aquatic green plants in your fish tank. You decide to expose two of the plants to green light and two to blue light. You want to determine which type of light is best for the light reactions, so to reach your conclusions, you decide to record the amount of oxygen bubbles produced. Which of the following results would be expected? There would be the same number of bubbles from plants in blue or green light. No bubbles would be produced in either green light or blue light. There would be more bubbles from the plants in green light than from those in blue light. There would be more bubbles from the plants in blue light than from those in green light.

There would be more bubbles from the plants in blue light than from those in green light.

The carotenoids and other accessory pigments in the chloroplast help capture light into the reaction center's chlorophyll molecules. True False

True

The majority of the leaf's chloroplasts are found in the mesophyll cells. True False

True

The photosystems are involved in the light reactions of photosynthesis. True False

True

All of the following factors influence the rate of photosynthesis EXCEPT temperature. light intensity. atmospheric N2 levels. water availability. atmospheric CO2 levels.

atmospheric N2 levels.

Light-harvesting pigments in the chloroplast include chlorophyll and the yellowish accessory pigments called ________.

carotenoids

The process of photosynthesis converts solar energy to ________ energy stored in the bonds of glucose.

chemical bond

During the process of photosynthesis, solar energy is converted to chemical energy. nuclear energy. heat energy. thermal energy. mechanical energy.

chemical energy.

________ is the main light-capturing molecule in chloroplasts and is responsible for giving leaves their characteristic green color.

chlorophyll

A pigment that absorbs red and blue light and reflects green light is carotenoid. melanin. chlorophyll. phycocyanin. xanthophyll.

chlorophyll.

The cellular organelle that utilizes sunlight to convert carbon dioxide and water into sugar and oxygen is the mitochondrion. thylakoid. chloroplast. endoplasmic reticulum. cristae.

chloroplast.

Albino corn has no chlorophyll. You would expect albino corn seedlings to eventually die because they cannot capture light energy. use accessory pigments such as carotenoids to capture light. capture light energy in the white end of the visible light spectrum. switch from the C4 pathway to the crassulacean acid metabolism (CAM) pathway. synthesize glucose indefinitely, using stored ATP and NADPH.

eventually die because they cannot capture light energy.

The products of photosynthesis are carbon dioxide, water, and energy. carbon dioxide, chlorophyll, and oxygen. glucose and carbon dioxide. glucose and water. glucose, water, and oxygen.

glucose, water, and oxygen.

The vast majority of chloroplasts found in a leaf are in the cuticle. mesophyll. stroma. vascular bundles. epidermis.

mesophyll.

All of the following compounds are necessary components for photosynthesis EXCEPT carbon dioxide. NADP. oxygen. ATP. water.

oxygen.

In the chloroplast, energy in sunlight is passed around different chlorophyll molecules until it reaches a specific chlorophyll molecule that can transfer energy in sunlight to an energized electron. This chlorophyll molecule is called the electron-carrier molecule. reaction center. accessory pigment. photoelectric point. nucleus.

reaction center.

Many plants have evolved leaves that have adjustable pores, called ________, which allow for gas exchange and water loss.

stomata

Carotenoid pigments are found in the mitochondria. nucleus. stroma of the chloroplasts. thylakoid membranes of the chloroplasts.

thylakoid membranes of the chloroplasts.

Specifically, molecules of chlorophyll are located in the membranes of sacs called vesicles. stoma. grana. thylakoids. stroma.

thylakoids.

The energy required for photosynthesis to occur is oxygen. air. glucose. ultraviolet light. visible light.

visible light.