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Questions | Answers

1. Converting solar energy to chemical energy by the following formula:
CO2 + H2O + solar energy >> Sugar + O2

2. Converting chemical energy into energy the body can use by the following formula: Sugar + O2 >> CO2 + H2O + energy

3. Pores in plant tissues through which plants exchange gasses (breathe).

4. Transpiration

5. The ratio of photosynthesis to transpiration. In other words, how much CO2 is brought into the plant as a ratio of how much water is lost from the plant through the stomata.

6. It occurs when the photosynthetic enzyme, RUBISCO, reacts with O2 (causing respiration, loss of energy) instead of CO2 (which would have caused photosynthesis and a gain of energy). Photorespiration limits the rate of photosynthesis at high light intensities and high leaf temperatures in most plants.

7. It is most efficient under normal conditions.

8. Brings in CO2 during the day using RUBISCO.

9. Most plants.

10. Photosynthesizes faster under high light/heat
Has greater water use efficiency

11. Photosynthesizes faster under high light/heat: C4 plants eliminate photorespiration by using PEP carboxylase to "hand-deliver" CO2 directly to RUBISCO (thus RUBISCO cannot grab O2 and so cannot photorespire).
Has greater water use efficiency: Because PEP carboxylase pulls in CO2 faster, the stomata don't have to stay open as much, thus reducing loss of water by transpiration thus increasing water use efficiency.

12. Many summer annual plants and grasses in our region.

13. Has greater water use efficiency
Can CAM idle

14. Has greater water use efficiency: Brings in CO2 (using PEP carboxylase) at night when evaporation rates are lower. CO2 is converted into acid that is stored until daytime when CO2 is released to RUBISCO for photosynthesis.
CAM Idling: CAM plants can keep their stomata closed all the time and still survive for a while by storing CO2 produced by respiration and then using the CO2 again for photosynthesis.

15. Many succulents like cactuses, agave, yuccas, and also orchids and bromeliads.

16. They have many sepals and petals that blend into each other, they have many anthers (usually hundreds), they have several to many stigma lobes, and they have areoles (modified branch containing buds, hairs, and spines).

17. Most are evergreen leaf succulents with spine-tipped leaves arranged in a rosette.

18. Agave: flower once in lifetime, and most are pollinated by bats. Yucca: flower annually, and are pollinated by a yucca moth.

19. They add nitrogen to the soil by forming a mutualistic relationship with nitrogen-fixing bacteria. They house the bacteria in root nodules.

20. Fabaceae.

21. Nurse plants provide shelter from freezing temperatures, intense sunlight, trampling, etc. to other plants. .