Chapter 7 Guided Reading Activity - Honors Bio

____________ reacts with ozone to turn it into ____________.

Chlorine; O2

Refer to the picture; What molecules do the two people at the top of the platforms represent?

They represent primary electron acceptors

A plant uses the products of the Calvin cycle for what?

To make starch, cellulose, and molecules used in protein synthesis

True or false: More than half of the world's plant and animal species live in tropical rain forests

True

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

chloroplasts

__________________is a long term change of the global climate for long periods of time.

climate change

True or false: A photoautotroph is a type of heterotroph that uses solar energy to produce sugars

false, a photoautotroph is not a heterotroph. Of course, it would be an autotroph.

True or false: Overall, photosynthesis is exergonic

false; cellular respiration is exergonic

True or false: C6H12O6 becomes oxidized in photosynthesis.

false; this happens in cellular respiration

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 chemical reactions of the Calvin cycle do not directly depend on solar energy, the reactions do depend on the products produced by the light reactions

Briefly explain what would happen to the levels of NADPH and ATP within the stroma if the passage of electrons to the primary electron acceptor of photosystem I were inhibited.

Because the continuous passing of electrons along the electron transport chain powers the production of ATP, ATP production would stop. Additionally, because the electron transport chain links photosystem II to photosystem I, any interruption in the transport chain would also halt NADPH production.

What are the similarities between C4 and CAM?

Both are adaptations to photosynthesis in hot and/or dry climates.

What are the differences between C4 and CAM?

C4 keeps the stomata closed most of the time during hot and dry periods and it continues to produce sugar because of an enzyme that has a high affinity for CO2 even when CO2 is low; CAM opens the stomata only at night to minimize water loss.

In photosynthesis, __________ is reduced.

CO2

A toxin is found to inhibit the uptake of CO2 into plant leaves. This toxin would most directly affect the .

Calvin cycle

A student has been shrunk to fit inside the thylakoid space of a granum. How many layers of phospholipids would he or she need to cross through to get completely out of the mesophyll cell?

Eight layers of phospholipids

True or false: During photosynthesis, CO2 is split to release oxygen gas.

False, O2 gas is created as a result of splitting H2O.

True or false: Each turn of the Calvin cycle produces one molecule of glucose.

False, one turn of the Calvin cycle makes a 3-carbon sugar called G3P. It would take two turns of the Calvin cycle to make a 6-carbon glucose.

True or false: Red wavelengths of light have more energy than purple wavelengths of light.

False, red wavelengths of light have less energy than violet (purple) wavelengths.

List three benefits of photosynthetic products to humans.

Food, fuel, and removal of CO2 from the atmosphere

A botanist discovers a new plant species in the Amazon rainforest 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 pigments in this plant absorb all wavelengths of the visible light spectrum except blue because that is the only color that is not absorbed

The picture clearly depicts the events that occur when a pigment absorbs a photon of light. If a substance somehow kept the boosted electron from falling back to its ground state, would light and heat still be released in the same amount? Briefly explain your answer.

No, if an electron were kept from falling back to its ground state, the energy would not be given off as light and heat in that moment

What are the differences between Photosystem I and II?

PI produces NADPH; PII produces ATP and splits water

The Calvin cycle is cyclic because...?

RuBP is regenerated in the final chemical reaction. (step 4)

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 bacteria are likely photoautotrophs and perform photosynthesis

What is the overall effect of increased CO2 levels on poison ivy growth?

The effect has been a significant increase in the growth of poison ivy

What links photosystem I with photosystem II?

The electrons passed between the two photosystems

Briefly explain what links the two stages of photosynthesis with each other.

The two stages of photosynthesis are linked by the ATP and NADPH produced in the light reactions. ATP and NADPH are used in the dark reactions to power the synthesis of sugar.

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. (greenhouse effect = added warmth to the earth)

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

b. Carbon dioxide

The two complexes of pigments that constitute a photosystem include ________________ and the __________________.

light-harvesting complex; reaction-center complex

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

photorespiration

If a scientist removes the pair of chlorophyll a molecules from the reaction-center complex, then what would most likely occur?

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

What do Photosystem I and II have in common?

they both Consist of two complexes of pigments and they're both linked by an electron transport chain.

True or false: photosynthesis is endergonic.

true