CAM Plants and CAM Photosynthesis
An Alternative to C3 is CAM Photosynthesis
CAM photosynthesis is also an adaptation to hot, dry climates. The plants that participate in this kind of photosynthesis open their stomata at night and close them during the day, so that they experience water loss during the day when the sun is out. (Non-CAM plants do the opposite of this). Because their stomata are closed during the day, Carbon Dioxide can’t get into the leaves during the day-so that they take it up at night.
CAM Cycle:
CAM plants take Carbon Dioxide into their leaves at night, convert it to various organic compounds and put it into temporary storage in their vacuoles. When morning comes and their stomata close, these plants release the stored Carbon Dioxide so that they can use light energy to perform the normal reactions of photosynthesis.
CAM Plants:
In both C4 and CAM photosynthesis, Carbon Dioxide is first transformed into an organic intermediate before it enters the Calvin Cycle. All of the processes-C3, C4 and CAM photosynthesis- use the Calvin Cycle; they just have different methods for getting there.
The difference is that in C4 plants, the intial steps of carbon fixation are separated structurally from the Calvin Cycle, whereas in CAM plants, the two steps occur at separate times but within the same cell. But, as stated above, CAM, C4, and C3 plants all eventually use the Calvin Cycle to make sugar from Carbon Dioxide.
Questions:
1. All of the following are considered CAM plants, except:
a. Pineapple
b. Cacti
c. Succulent Plants
d. Sugar Cane
2. Which of the following is true concerning CAM Plants:
a. CAM plants open their stomata during the day
b. During the day, CAM plants take up Carbon Dioxide and form organic acids
c. CAM plants close their stomata during the day
d. During the night, CAM plants take up Carbon Dioxide and form organic acids
e. Both (a) and (d) are correct
3. How is the CAM pathway similar to the C4 pathway?
a. Carbon Fixation and the Calvin Cycle both occur in different types of cells
b. Carbon Fixation and the Calvin Cycle both occur in the same cell at different times
c. Carbon Dioxide is first incorporated into organic intermediates before it enters the Calvin Cycle
d. The initial steps of carbon fixation are separated structurally from the Calvin Cycle
4. What are the solutions to maintaining photosynthesis with stomata partially or completely closed on hot, dry days?
a. Chemiosmosis
b. C3 plants and C4 plants
c. C4 plants and CAM plants
d. Only CAM plants
e. Only C3 Plants
Answers: d, e, c, c
Just a reminder that tomorrow is the in-class comprehensive essay. After that, we will have two in-class, open-book quizzes. Hope you had a great weekend!
An Alternative to C3 is CAM Photosynthesis
CAM photosynthesis is also an adaptation to hot, dry climates. The plants that participate in this kind of photosynthesis open their stomata at night and close them during the day, so that they experience water loss during the day when the sun is out. (Non-CAM plants do the opposite of this). Because their stomata are closed during the day, Carbon Dioxide can’t get into the leaves during the day-so that they take it up at night.
CAM Cycle:
CAM plants take Carbon Dioxide into their leaves at night, convert it to various organic compounds and put it into temporary storage in their vacuoles. When morning comes and their stomata close, these plants release the stored Carbon Dioxide so that they can use light energy to perform the normal reactions of photosynthesis.
CAM Plants:
In both C4 and CAM photosynthesis, Carbon Dioxide is first transformed into an organic intermediate before it enters the Calvin Cycle. All of the processes-C3, C4 and CAM photosynthesis- use the Calvin Cycle; they just have different methods for getting there.
The difference is that in C4 plants, the intial steps of carbon fixation are separated structurally from the Calvin Cycle, whereas in CAM plants, the two steps occur at separate times but within the same cell. But, as stated above, CAM, C4, and C3 plants all eventually use the Calvin Cycle to make sugar from Carbon Dioxide.
Questions:
1. All of the following are considered CAM plants, except:
a. Pineapple
b. Cacti
c. Succulent Plants
d. Sugar Cane
2. Which of the following is true concerning CAM Plants:
a. CAM plants open their stomata during the day
b. During the day, CAM plants take up Carbon Dioxide and form organic acids
c. CAM plants close their stomata during the day
d. During the night, CAM plants take up Carbon Dioxide and form organic acids
e. Both (a) and (d) are correct
3. How is the CAM pathway similar to the C4 pathway?
a. Carbon Fixation and the Calvin Cycle both occur in different types of cells
b. Carbon Fixation and the Calvin Cycle both occur in the same cell at different times
c. Carbon Dioxide is first incorporated into organic intermediates before it enters the Calvin Cycle
d. The initial steps of carbon fixation are separated structurally from the Calvin Cycle
4. What are the solutions to maintaining photosynthesis with stomata partially or completely closed on hot, dry days?
a. Chemiosmosis
b. C3 plants and C4 plants
c. C4 plants and CAM plants
d. Only CAM plants
e. Only C3 Plants
Answers: d, e, c, c
Just a reminder that tomorrow is the in-class comprehensive essay. After that, we will have two in-class, open-book quizzes. Hope you had a great weekend!
No comments:
Post a Comment