BIO 1408 Chapter 5 Review

What two pathways minimize photorespiration rate by ensuring that rubisco always encounters high CO2 concentration?

***A. C4 pathway ***B. CAM pathway C. Calvin cycle D. C3 pathway

The carbon reactions of photosynthesis are also known as the ______, which occur in the stroma of chloroplasts.

***A. Calvin cycle B. Krebs cycle C. Cam cycle D. Crick cycle

Select the names of the two stages of photosynthesis.

***A. Carbon reactions ***B. Light reactions C. Krebs cycle D. Respiration reactions

Select all of the components of a photosystem.

***A. Chlorophyll pigments ***B. Proteins ***C. a reaction center chlorophyll D. Stomata and guard cells ***E. Accessory pigments

At the end of the electron transport chain of the light reactions, electrons reduce NADP+ and form ________.

NADPH

Oxygen from photosynthesis combines with free oxygen atoms in the atmosphere to produce ______, which shields Earth from harmful UV radiation.

Ozone

Light consists of ________, which are discrete packets of kinetic energy.

Photons

Select all of the ways that photosynthesis is critical to life on Earth.

***A. Provides food for heterotrophs that eat photosynthesizers. ***B. Provides food for photosynthesizers. ***C. Incorporates atmospheric CO2 into organic compounds. D. Provides the carbon dioxide used by almost all organisms. ***E. Produces oxygen essential to many forms of life.

Select all of the following that are photosynthetic organisms.

***A. Some groups of bacteria ***B. Algae ***C. Plants D. Fungi E. Some types of animals

What statement accurately describes how the two photosystems function in the light reactions?

***A. They function sequentially, with photosystem II acting first B. They function separately, with the activities of photosystem I not affecting photosystem II. C. They function separately, with the activities of photosystem II not affecting photosystem I. D. They function sequentially, with photosystem I acting first.

Place the following events in the correct order in which they occur in photosystem I, beginning with the first event at the top.

1. Antenna pigments capture a photon of light. 2. Energy is passed to the electrons of the reaction center. 3. Two excited electrons are passed along the electron transport chain.

Place the following events in the correct order in which they occur in the C4 pathway, beginning at the top with the fixation of carbon into a four-carbon molecule.

1. CO2 is combined with a three-carbon molecule, forming the four-carbon molecule oxaloacetate. 2. Oxaloacetate is usually reduced to malate. 3. Malate moves to bundle-sheath cells away from O2 rich air spaces. 4. CO2 is liberated and then fixed again as it enters the Calvin cycle.

Place the following events in the correct order in which they occur in the CAM pathway.

1. Carbon dioxide diffuses into leaves when stomata are open at night. 2. Carbon dioxide is stored as Malate in vacuoles within mesophyll cells. 3. Malate is moved from the vacuoles to the chloroplasts of mesophyll cells and then carbon dioxide is released. 4. The chloroplasts can then fix carbon dioxide in the Calvin cycle, even when the stomata are closed during the day.

Match the photosynthetic pigments with their correct descriptions.

1. Chlorophyll a: most abundant pigment in plants; reflects green wavelengths of light. 2. Chlorophyll b: accessory pigments that reflects green wavelengths of light. 3. Carotenoids: accessory pigments that reflect red, orange, and yellow wavelengths of light.

Place the following events in the correct order in which they occur during the electron transport chain between photosystem II and photosystem I.

1. The electron transport chain receives energized electrons from photosystem II. 2. The electrons are shuttled through a series of proteins in the thylakoid membrane. 3. The energy lost from the electrons drives the active transport of protons from the stroma into the thylakoid space. 4. The electrons arrive at photosystem I.

Place the following events in the correct order in which they occur in the Calvin cycle, beginning at the top with the carbon fixation step.

1. The enzyme rubisco combines carbon dioxide with RuBP to form a 6-carbon unstable molecule. 2. The 6-carbon molecule splits to form PGA. 3. PGA is converted into PGAL. 4. Some PGAL is converted into glucose and other sugars, and some PGAL is converted back to RuBP.

Match each chloroplast structure with its correct description.

1. Two membranes: surround each chloroplast 2. Stroma: fluid matrix within the chloroplasts 3. Thylakoids: stacked within stroma and studded with pigment molecules 4. Thylakoid space: volume enclosed by thylakoid membranes

Match the component of sunlight with the correct description.

1. Ultraviolet radiation: photons are high-energy and can damage DNA. 2. Visible light: photons provide energy for photosynthesis. 3. Infrared radiation: photons contain little energy, which is mostly converted to heat.

Rank the following comments of the electromagnetic spectrum from greatest amount of energy at the top to the least amount of energy at the bottom.

1. X-rays 2. Ultraviolet radiation 3. Visible light 4. Infrared radiation 5. Microwaves

The Calvin cycle is also called

A. The C4 pathway ***B. The c3 pathway C. The light reactions D. Photorespiration

C3 plants are plants that

A. Use the c3 pathway to fix carbon but aren't affected by photorespiration. ***B. Only use the c3 pathway to fix carbon. C. Use the CAM pathway and the Calvin cycle to fix carbon. D. Are able to use both the c3 and C4 pathways to fix carbon.

ATP synthase produces ATP during photosynthesis and aerobic cellular respiration in a process called

A. ADP hydrolysis ***B. Chemlosmotic phosphorylation C. Beta-oxidation D. Dehydration synthesis

In the light reactions, pigments molecules in a photosystems capture photons of light, and energy from light becomes stored as potential energy in

A. ATP and NADH ***B. ATP and NADPH C. ATP and glucose D. NADH and FADH2

The green, photosynthetic pigment found in plants, algae, and Cyanobacteria is called

A. Bacteriohodopsin ***B. Chlorophyll a C. Phycobilin D. Cytochrome c

What is generated using the energy of electrons at the end of the electron transport chain in the light reactions of photosynthesis?

A. Carbon dioxide ***B. NADPH C. Water D. Light energy

What occurs during photorespiration that stops the Calvin cycle from proceeding?

A. Carbon dioxide binds to the active site of rubisco. B. Carbon dioxide concentration within leaves rises. C. High oxygen levels inhibit the light reactions, and NADPH is not produced. ***D. Rubisco adds oxygen instead of carbon dioxide to RuBP.

During the photosynthetic electron transport chain, protons are pumped into the ________ from the stroma and then pass back to the stroma through _________ channels, which are enzyme complexes that can use the energy released from the protons to generate ATP.

A. Cell cytoplasm; rubisco ***B. Thylakoid space; ATP synthase C. Thylakoid space; rubisco D. Cell cytoplasm; ATP synthase

What molecule produced by the light reactions stores potential energy in the covalent bonds between its phosphate groups?

A. Chlorophyll B. Glucose ***C. ATP D. Carbon Dioxide

What molecules produced by the light reactions stores potential energy in the covalent bonds between its phosphate groups?

A. Chlorophyll B. Glucose C. Carbon dioxide ***D. ATP

What type of organism has the ability to produce organic compounds from inorganic substances?

A. Consumers B. Heterotrophs ***C. Autotrophs D. Fungus

The purple structure indicated by the arrow in the diagram is an enzyme called __________, which adds a phosphate to ADP using energy from a proton gradient.

A. Creatine phosphate B. Rubisco C. Luciferase ***D. ATP Synthase

In the light-independent reactions of photosynthesis, the __________ is a series of reactions in which the first stable compound formed is a 3-carbon molecule (PGA).

A. Electron transport chain B. C4 pathway C. CAM Pathway ***D. C3 pathway

In carbon reactions of photosynthesis, carbon from _________ is used to produce sugar molecules using energy from ATP and electrons from NADPH.

A. Glucose B. Oxygen gas ***C. Carbon dioxide D. NAD+

Light energy that is captured in photosynthesis is converted to _________ energy stored in the chemical bonds of molecules.

A. Kinetic ***B. Potential C. Solar D. Sound

Select all of the molecules that are reactants of photosynthesis.

A. Malate (C4H6O5) ***B. Carbon Dioxide (CO2) ***C. Water (H2O) D. Oxygen (O2) E. Glucose (C6H12O6)

In plants, molecules called pigments are able to capture _______ for photosynthesis.

A. NADPH B. Water C. Carbon dioxide ***D. Light energy

Select all of the following that are typically or always heterotrophs.

A. Plants B. Algae ***C. Fungi ***D. Animals

Within a photosystem, what pigments capture photon energy and funnel the energy to the reaction center chlorophyl?

A. Production pigments ***B. Antenna pigments C. Retinal pigments D. Oxygen-binding pigments

Electron transport chains release _________ through shuttling of electrons in the light reactions.

A. RuBP B. Photons ***C. Energy D. Carbon dioxide

The ________ reactions of photosynthesis use ATP and NADPH to reduce carbon dioxide to sugar molecules.

A. electron transport chain ***B. Carbon C. Krebs D. Light

The enzyme rubisco adds oxygen instead of carbon dioxide to RuBP in a process called

A. the CAM pathway B. carbon fixation ***C. Photorespiration D. the C4 Pathway

The Calvin cycle cannot proceed without the molecules _____ and ______, which are produced by the light reactions of photosynthesis.

ATP and NADPH

Organisms called ________ are able to use inorganic molecules to make organic compounds.

Autotrophs

In C4 plants, the Calvin cycle takes place within ________ sheath cells, which are not exposed directly to atmospheric oxygen and therefore rubisco binds more often to carbon dioxide, reducing photorespiration.

Bundle

Match the pathway with the correct description.

C4 photosynthesis: carbon dioxide is used to produce oxaloacetate, and the Calvin cycle takes place in the bundle-sheath cells. CAM photosynthesis: carbon dioxide is incorporated into a 4-carbon molecule at night, and the Calvin cycle takes place during the day in mesophyll cells.

In plants and algae, photosynthesis takes place in organelles called ________, which contain thylakoid membranes embedded with the pigment chlorophyll.

Chloroplast

During the light reactions, energized __________ from a reaction center chlorophyll a molecule are eventually donated to form the molecule NADPH.

Electrons

When pigments in photosystem II absorb light energy, __________ are boosted to a higher energy level and passed to the electron transport chain that links the two photosystems.

Electrons

Match the pathway with the correct description.

Photorespiration: oxygen is used by the enzyme rubisco in an energetically wasteful reaction. C3 pathway: carbon dioxide is used by the enzyme rubisco to produce PGA.

In a metabolic process called ____________, plants, algae, and some types of bacteria convert solar energy into chemical energy, such as glucose.

Photosynthesis

In a photosystem, antenna pigments capture photon energy and funnel it to the _________ center, which consists of a pair of chlorophyll a molecules that actually use the light energy in photosynthetic reactions.

Reactions

Plants conduct gas exchange in photosynthesis by bringing in carbon dioxide and releasing oxygen through openings called __________.

Stomata

The openings in the epidermis of a leaf or stem for gas exchange are called ___________.

Stomata

Within the chloroplasts, the gelatinous fluid containing DNA, ribosomes, and enzymes is called the _________.

Stroma

The oxygen by-product of photosynthesis is created by the splitting of ________ molecules to replace the electrons ejected from the reaction center of photosystem II.

Water

Photosynthetic pigments absorb different ___________ of visible light.

Wavelengths