Carbon Fixing Adaptations Flashcards
1
Q
Summary of “C3” plants
A
- Plants that grow in average cool to warm conditions
- CO2 is fixed in the Calvin cycle via rubisco
2
Q
What happens to plants in hot, dry environments?
A
- Plants tend to close their stomata to prevent water-loss through transpiration
- This results in less or very little CO2 fixation and a build up of O2 inside the leaf
3
Q
Photorespiration
A
Process by which plants revert to a different form of respiration rather than photosynthesis
4
Q
Why does photorespiration happen?
A
Because oxygen is high and carbon dioxide is low in the plant cells
5
Q
What does “C3” refer to?
A
- To the 3 carbon (PGA or G3P) intermediate molecule that eventually forms glucose
6
Q
Examples of C3 plants
A
- Kentucky bluegrass
- Tomatoes
- Rice
- Barley
- Wheat
- Soybean
- Potatoes
7
Q
Advantages of C3 plants
A
- Thrive at medium to low temps
- (up to 25 degrees average)
8
Q
Disadvantages of C3 plants
A
- When temps are high CO2 lowers and photorespiration occurs
- Decreases productivity
9
Q
What are C4 plants also called?
A
- Floridian plants
- Tropical plants
10
Q
Summary of C4 plants
A
- CO2 is fixed twice in two different types of cells
11
Q
What are the 2 types of cells that fix CO2 in C4 plants?
A
- Mesophyll Cells
- Bundle Sheath Cells with Chloroplasts
12
Q
First carbon fixation in C4 plants
A
- CO2 is attached to PEP which turns into oxaloacetate which is a 4 carbon molecule
13
Q
Second carbon fixation in C4 plants
A
- CO2 is released into the bundle sheath cells where typical Calvin cycle occurs
14
Q
Examples of C4 plants
A
- Crabgrass
- Corn
- Many tropical shrubs
15
Q
Advantages of C4 plants
A
- Plants can have smaller stomata and they don’t need to be open as long
- Water loss is lower and photorespiration does not occur
- More productive
