3/26 lecture

Question 1

How do plants avoid photorespiration?

Answer 1

plants have evolved variations on photosynthesis to survive in hot, dry climates;
Rubsico from plants in arid or saline environments fix less O2 per CO2

Question 2

C3 photosynthesis

Answer 2

photosynthesis where carbon is first fixed into a six-carbon sugar (~85% of plants, ancestral state)

Question 3

C4 photosynthesis

Answer 3

variation of photosynthesis where carbon is first fixed into a 4-carbon acid by PEP-carboxylase (~3% of plants)

Question 4

CAM photosynthesis

Answer 4

variation of photosynthesis where carbon is first fixed into a 4-carbon acid by PEP-carboxylase IN THE DARK (~8% of plants)

Question 5

What types of photosynthesis are better in hot climates? Why?

Answer 5

C4 and CAM (they do less photorespiration at high temperatures and conserve more water

Question 6

What type of plants are most susceptible to light damage at low temps?

Answer 6

tropical C4 plants