B8 Photosynthesis

Question 1

Complete the equation for photosynthesis

carbon dioxide + ___ (+ light) → glucose + ___

Answer 1

carbon dioxide + water (+ light) → glucose + oxygen

Question 2

What is the purpose of a water bath in experiments?

Answer 2

To keep temperature constant.

Question 3

What are the three main limiting factors of photosynthesis?

Answer 3

Light intensity
Temperature
Carbon dioxide concentration in air

Question 4

A student monitors the rate of photosynthesis as he increases the light intensity. Eventually, the rate of photosynthesis no longer increases. Why?

Answer 4

Another factor other than light intensity has become the limiting factor.

Question 5

A student investigated the effect of light intensity on the rate of photosynthesis. Using a lamp he changed the distance of the lamp from the pondweed. Why did he choose to place the pondweed in a water bath?

Answer 5

To ensure the heat given out by the lamp didn’t also change the temperature of the pond weed.

Question 6

How do you know when a factor is no longer the limiting factor for photosynthesis?

Answer 6

When you change it there is no further change in the rate of photosynthesis.

Question 7

The source of energy for (outdoor) green plants is radiation from the ____.

Answer 7

sun

Question 8

Green plants absorb some of the light energy that reaches them for a process called ____.

Answer 8

photosynthesis

Question 9

Photosynthesis transfers light energy into ____ energy.

Answer 9

chemical

Question 10

Photosynthesis uses the gas ____.

Answer 10

carbon dioxide

Question 11

Photosynthesis produces carbon-containing compounds called _____.

a) carbohydrates
b) minerals
c) salts
d) cheese toasties

Answer 11

a) carbohydrates

Question 12

Photosynthesis produces the gas ____.

Answer 12

oxygen

Question 13

Chlorophyll absorbs ___ light.

a) white
b) green
c) red and blue

Answer 13

c) red and blue

Question 14

Chlorophyll reflects ___ light.

a) white
b) green
c) red and blue

Answer 14

b) green