Biology GRA answers Chapter 7 test
____________ reacts with ozone to turn it into ____________
Chlorine Oxygen
What do photosystems II and I have in common?
Consist of two complexes of pigments. Linked by an electron transport chain.
A plant uses the products of the Calvin cycle for:
To make starch To make cellulose To make molecules used in protein synthesis
A plant's leaves are the primary site of photosynthesis. A plant's leaves would be expected to have a large amount of ____________.
chloroplasts (A student could also make an argument for chlorophyll.)
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.
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
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 do C4 and CAM have in common?
Both are adaptations to photosynthesis in hot and/or dry climates
What makes C4 different from CAM?
C4 keeps the stomata closed most of the time during hot and dry periods. Continues to produce sugar because of an enzyme that has a high affinity for CO2 even when CO2 is low.
What makes CAM different from C4?
CAM opens the stomata only at night to minimize water loss.
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. If false, make it a correct statement.
False, O2 gas is created as a result of splitting H2O
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 photoautotroph is not a heterotroph. Of course, it would be an autotroph.
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
True or false: The Kyoto Protocol of 1997 eliminated the use of CFCs by all participating countries.
False, the Montreal Protocol eliminated the use of CFCs by all participating countries.
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.
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 makes photosystem I different from photosystem II?
Photosystem I produces NADPH.
What makes photosystem II different from photosystem I?
Photosystem II produces ATP and Splits water.
The Calvin cycle is cyclic because
RuBP is regenerated in the final chemical reaction.
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.
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?
The primary electron acceptor would capture boosted electrons from the light-harvesting complex.
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.
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
