Chapter 5 review questions
4. From where does a heterotroph directly obtain its energy? A. the sun B. the sun and eating other organisms C. eating other organisms D. simple chemicals in the environment
C is the correct answer
12. What is the overall purpose of the light reactions in photosynthesis?
the overall purpose of the light reactions are to produce ATP and NADPH
10. Which statement correctly describes carbon fixation? A. the conversion of CO2 to an organic compound B. the use of RuBisCO to form 3-PGA C. the production of carbohydrate molecules from G3P D. the formation of RuBP from G3P molecules E. the use of ATP and NADPH to reduce CO2
A is the correct answer
7. Plants produce oxygen when they photosynthesize. Where does the oxygen come from? A. splitting water molecules B. ATP synthesis C. the electron transport chain D. chlorophyll
A is the correct answer
3. Which statement about thylakoids in eukaryotes is not correct? A. Thylakoids are assembled into stacks. B. Thylakoids exist as a maze of folded membranes. C. The space surrounding thylakoids is called stroma. D. Thylakoids contain chlorophyll.
B is correct
11. What is the molecule that leaves the Calvin cycle to be converted into glucose? A. ADP B. G3P C. RuBP D. 3-PGA
B is the correct answer
5. What is the energy of a photon first used to do in photosynthesis? A. split a water molecule B. energize an electron C. produce ATP D. synthesize glucose
B is the correct answer
8. Which color(s) of light does chlorophyll a reflect? A. red and blue B. green C. red D. blue
B is the correct answer
2. What two products result from photosynthesis? A. water and carbon dioxide B. water and oxygen C. glucose and oxygen D. glucose and carbon dioxide
C is the correct answer
6. Which molecule absorbs the energy of a photon in photosynthesis? A. ATP B. glucose C. chlorophyll D. water
C is the correct answer
9. Where in plant cells does the Calvin cycle take place? A. thylakoid membrane B. thylakoid space C. stroma D. granum
C is the correct answer
13. Why are carnivores, such as lions, dependent on photosynthesis to survive?
Carnivores such as lions are dependent on photosynthesis because the plant that does photosynthesis is eaten by an herbivore and then said herbivore is eaten by the lion
16. Explain the reciprocal nature of the net chemical reactions for photosynthesis and respiration.
Photosynthesis takes the energy of sunlight and combines water and carbon dioxide to produce sugar and oxygen as a waste product. The reactions of respiration take sugar and consume oxygen to break it down into carbon dioxide and water, releasing energy. Thus, the reactants of photosynthesis are the products of respiration, and vice versa.
14. Describe the pathway of energy in light-dependent reactions.
The energy is present initially as light. A photon of light hits chlorophyll, causing an electron to be energized. The free electron travels through the electron transport chain, and the energy of the electron is used to pump hydrogen ions into the thylakoid space, transferring the energy into the electrochemical gradient. The energy of the electrochemical gradient is used to power ATP synthase, and the energy is transferred into a bond in the ATP molecule. In addition, energy from another photon can be used to create a high-energy bond in the molecule NADPH.
15. Which part of the Calvin cycle would be affected if a cell could not produce the enzyme RuBisCO?
the part of the calvin cyle that would be affected is the reducing of the carbon dioxide and thus the rest of the cycle couldn't take place
1. Figure 5.7 On a hot, dry day, plants close their stomata to conserve water. What impact will this have on photosynthesis?
this will stop the inflow of carbon dioxide and thus stop photosynthesis until the stomata are reopened
