bioenergetics

Question 1

what is photosynthesis

Answer 1

an endothermic reaction in which energy is transferred from the environment to the chloroplasts by light.

Question 2

where does photosynthesis take place

Answer 2

in the leaves of the plant ( specifically the chloroplast )

Question 3

what happens in the stages of photosynthesis

Answer 3

1. carbon dioxide and water are taken into the leaf from the plant
2. light energy is then absorbed by chlorophyll
3. the light energy is used to convert carbon dioxide and water into glucose
4. the reaction also produces oxygen

Question 4

what is chlorophyll

Answer 4

a green- like pigment that absorbs light energy for photosynthesis

Question 5

what is the word equation for photosynthesis

Answer 5

carbon dioxide + water -light energy–>glucose + oxygen

Question 6

what is the symbol equation for photosynthesis

Answer 6

6C02 + 6H20 ->– C6 H12 06 + 602

Question 7

how does light intensity affect the rate of photosynthesis

Answer 7

1. when light intensity is zero the rate of photosynthesis is zero as plants need light to carry out photosynthesis
2. as we increase the light intensity the rate of photosynthesis increases because the plant has more light energy so the photosynthesis reaction is faster - this tells use that light intensity is the limited factor ( the rate of photosynthesis is limited by light intensity )
3. however if light intensity gets too great the rate of photosynthesis no longer increases and is plateaued / levelled this means there must be a different limiting factor

Question 8

how does carbon dioxide affect the rate of photosynthesis

Answer 8

as c02 concentration increases the rate of photosynthesis increases - this tells us that carbon dioxide was the limiting factor
- however, over time, the rate of photosynthesis no longer increases as carbon dioxide concentration is plentiful and so co2 is no longer the limiting factor

Question 9

how does temperature affect the rate of photosynthesis

Answer 9

as we increase the temperature the rate of photosynthesis increases as the enzymes

Question 10

what is the limiting factor :
- at night
- during winter
- on a sunny/warm day

Answer 10

• light
• temperature
• carbon dioxide concentration