11.5 - Limiting Factors

Question 1

What are the requirements for photosynthesis?

5 things

Answer 1

1. Photosynthetic pigments (e.g. chlorophyll) - These absorb light energy.
2. Carbon dioxide - This provides carbon to make glucose.
3. Water - This provides electrons and is a source of hydrogen ions (protons).
4. Light - This provides energy to split water, to produce ATP, and to reduce NADP.
5. A suitable temperature - This provides kinetic energy for reactions.

Question 2

What are the main limiting factors in photosynthesis?

Answer 2

• Light intensity
• Carbon dioxide concentration
• Temperature

Question 3

How does low light intensity affect photosynthesis?

Answer 3

Limits light-dependent stage

Question 4

How does intermediate light intensity affect photosynthesis?

Answer 4

Increases ATP and reduced NADP production

Question 5

How does very high light intensity affect photosynthesis?

Answer 5

Another factor becomes limiting

Question 6

What is the light compensation point?

Answer 6

Rate of photosynthesis equals rate of respiration

Question 7

How does low carbon dioxide concentration affect photosynthesis?

Answer 7

Limits light-independent reaction

Question 8

How does intermediate carbon dioxide concentration affect photosynthesis?

Answer 8

Increases GP and TP production

Question 9

How does high carbon dioxide concentration affect photosynthesis?

Answer 9

Another factor becomes limiting

Question 10

What is the saturation point?

Answer 10

Factor being measured is no longer limiting

Question 11

How does low temperature affect photosynthesis?

Answer 11

Slows enzyme-catalysed reactions

Question 12

How does intermediate temperature affect photosynthesis?

Answer 12

Increases kinetic energy

Question 13

How does very high temperature affect photosynthesis?

Answer 13

Denatures enzymes