Biology Ch. 7

Overall, this process is exergonic (energy-releasing)..

Cellular respiration is an exergonic process as it releases energy by the end of its reaction.

Oxygen is the final electron acceptor for cellular respiration. What is the final electron acceptor in the light reactions of photosynthesis?

NADP+

What transports electrons from the light reactions to the Calvin cycle?

NADPH

The light reactions of photosynthesis generate high-energy electrons, which end up in __________. The light reactions also produce __________ and __________.

NADPH : ATP : oxygen

The Calvin cycle describes the conversion of ___.

carbon dioxide to carbohydrates

C6H12O6 becomes oxidized in this process.

cellular respiration

A plant's leaves are the primary site of photosynthesis. A plant's leaves would be expected to have a large amount of _____.

chloroplast

________________ is a long-term change of the global climate for long periods of time.

climate change

Which of the following are photoautotrophs?

corn stalks before harvest. They produce organic molecules from inorganic molecules using the energy of light.

In C4 and CAM plants carbon dioxide is fixed in the _____ of mesophyll cells.

cytoplasm

A plant uses the products of the Calvin cycle for which of the following? a. To make starch b. To make cellulose c. To make molecules used in protein synthesis d. All of the above

d. all of the above

Photosynthesis is an __________ process in which carbon is __________, whereas cellular respiration is an __________ process in which carbon is __________.

endergonic : reduced : exergonic : oxidized

The primary function of light absorption by photosystems I and II is to produce __________.

free, energized electrons

Thylakoids are arranged in stacks called

grana

A botanist discovers a new plant species in the Amazon rain forest that has blue leaves. Briefly explain what can be inferred about the pigments in the leaves of this plant.

it can be assumed that the plant absorbs all colors except blue

Chlorophyll

A green pigment found in the chloroplasts of plants, algae, and some bacteria

What two molecules are produced by the light reactions and used to power the Calvin cycle?

ATP and NADPH

_____ _____ phosphorylates ADP.

ATP synthase

In ___ plants, the first product of carbon fixation is the three-carbon compound 3-PGA formed in the Calvin cycle.

C3

In _____ plants, CO2 is first fixed into a four-carbon compound, which moves into bundle-sheath cells and releases CO2 to the Calvin cycle.

C4

In _____ plants, stomata are open at night, and CO2 is first fixed into a four-carbon compound, which releases CO2 to the Calvin cycle during the day.

CAM

True or false: A photoautotroph is a type of heterotroph that uses solar energy to produce sugars. If false, make it a correct statement.

False, a phototroph is not a heterotroph

Each turn of the Calvin cycle produces one molecule of glucose. If false, make it a correct statement.

False, it takes six turns of the Calvin cycle to produce one molecule of glucose

True or false: Red wavelengths of light have more energy than purple wavelengths of light. If false, make it a correct statement.

False, red wavelengths of light have less energy than purple wavelengths because their wavelengths are longer, and violet's wavelengths are shorter

During photosynthesis, CO2 is split to release oxygen gas. If false, make it a correct statement.

False: O2 is produced from the splitting of H2O

List three benefits of photosynthetic products to humans.

Food, fuel, and removal of CO2 from the atmosphere

What provides electrons for the light reactions?

H2O

When such plants close their stomata on hot, dry days to conserve water, _____ builds up in the leaf and is added to RuBP in place of CO2. A two-carbon product of this reaction is broken down to CO2, consuming ATP and generating no sugar.

O2

Overall, this process is endergonic (energy-consuming).

Photosynthesis is endergonic because it absorbs light energy to start its reaction.

_____ _____ splits water into 1/2 O2, H+, and e- .

Photosystem II

Chlorophyll can be found in _____.

Photosystems I and II

Which of the following structures allows for gas exchange between the tissues of a leaf and the atmosphere?

Stomata

A new bacterium is discovered in Lake Superior. Scientists are able to determine that these bacteria produce oxygen gas. What is likely to be true about these organisms?

The bacterium is a phototroph that performs photosynthesis because it produces oxygen

If a scientist removes the pair of chlorophyll a molecules from the reaction-center complex, then which of the following consequences would be most likely to occur? a. The primary electron acceptor would capture boosted electrons from the light-harvesting complex. b. The transfer of energy from the light-harvesting complex to the reaction-center complex would stop. c. Light would be absorbed twice as fast to make up for the loss of the chlorophyll a pigments. d. None of the above consequences would occur.

a. The primary electron acceptor would capture boosted electrons from the light-harvesting complex.

The Calvin cycle is also referred to as the light-independent reactions. Briefly explain why referring to the chemical reactions of the Calvin cycle as the light-independent reactions is only partially accurate.

although the Calvin Cycle doesn't depend on solar energy it does depend on products produced with light energy

What is the name given to organisms that can make their own food and thus sustain themselves without consuming organic molecules derived from other organisms?

autotrophs

What links photosystem I with photosystem II? a. The products of the dark reactions b. An electron transport chain c. The creation of oxygen gas d. The fixation of carbon dioxide

b. An electron transport chain

Which of the following colors of light are used during the process of photosynthesis?

blue, red, and violet

A toxin is found to inhibit the uptake of CO2 into plant leaves. This toxin would most directly affect the _____. a. light reactions b. splitting of H2O c. Calvin cycle d. absorption of solar energy

c. Calvin cycle

1. The Calvin cycle is cyclic because a. CO2 is constantly acquired during carbon fixation b. it constantly makes G3P. c. RuBP is regenerated in the final chemical reaction. d. NADPH and ATP are used from the light reactions.

c. RuBP is regenerated in the final chemical reaction

Which of the following substances provides the majority of the atoms that make up the sugar produced by photosynthesis? a. Water b. Carbon dioxide c. Oxygen d. Hydrogen

c. carbon dioxide

the 2 complexes of pigments that constitute a photo-system include _______ and ________

light-harvesters, reaction center

Phototrophs

obtain energy from light, the producers of food consumed by heterotrophic organisms

Heterotroph

organism that obtains energy from the foods it consumes; also called a consumer

Autotrophs that utilize light as their energy source are

photoautotrophs.

In C3 plants the conservation of water promotes _____.

photorespiration

The apparently wasteful process described in sentence 2 is called ______ .

photorespiration

___________________ is the process by which a plant adds O2 to RuBP instead of CO2.

photorespiration

CO2 is reduced in this process

photosynthesis

Energized electrons from _____ _____ are used to reduce NADP+.

photosystem I

In all three types of plants, the enzyme _____ brings CO2 into the Calvin cycle.

rubisco

Carbon dioxide enters a leaf through the _____.

stomata

The photosynthetic event known as the Calvin cycle occurs in the __________.

stroma

The energy released as electrons are passed along the electron transport chain is used to pump protons into the _____ compartment.

thylakoid

Chlorophyll is located in ________, which are found in ________, which are concentrated in ________.

thylakoids; chloroplasts; mesophyll

The light reactions take place in the _________ and the Calvin cycle takes place in the _________.

thylakoids; stroma

C4 plants differ from C3 and CAM plants in that C4 plants _____.

transfer fixed carbon dioxide to cells in which the Calvin cycle occurs

True or false. Guard cells open during the day to allow gases to flow through the stomata.

true

True or false: More than half of the world's plant and animal species live in tropical rain forests. If false, make it a correct statement.

true

Both mitochondria and chloroplasts _____.

use an H+ gradient to produce ATP

A common misconception is that the greenhouse effect is bad. Briefly explain why this is not necessarily true.

without the greenhouse effect, the earth would be significantly cooler and not as hospitable to life as we know it.