Quiz 35

Question 1

When investigating the effect of light intensity on rate of photosynthesis, how is it changed?

Answer 1

By varying distance between the light source and the pondweed

Question 2

What is the glucose made in photosynthesis used for?

Answer 2

Cellular production, respiration, oil and fat production, protein synthesis and stored as starch

Question 3

When investigating the effect of light intensity on the rate of photosynthesis, what is the dependent variable ?

Answer 3

The rate of photosynthesis

Question 4

When investigating the effect of light intensity on the rate of photosynthesis, what is the independent variable?

Answer 4

Light intensity

Question 5

Explain the effect of carbon dioxide concentration on the rate of photosynthesis

Answer 5

As carbon dioxide concentration increases, the rate of photosynthesis also increases up to a maximum level. This is because plants need carbon dioxide to photosynthesise After this point, the rate levels off because another factor is limiting the rate of photosynthesis .

Question 6

Explain how iodine solution can be used to determine if is taking place in a section of a leaf

Answer 6

Photosynthesising parts of a leaf will produce glucose, which is converted to insoluble starch for storage. Iodine solution can be used to test for starch. If the iodine changes from reddish-orange to blue black, starch is present which means photosynthesis has taken place

Question 7

Write the word equation for photosynthesis

Answer 7

Water + carbon dioxide —-> glucose + oxygen

Question 8

Explain the effect of temperature on the rate of photosynthesis

Answer 8

As temperature increases, the rate of photosynthesis also increases until it reaches a maximum level. At temperatures higher than this point, enzymes denature and the rate of photosynthesis decreases

Question 9

In terms of the effect of the light intensity on plants, what is the inverse square law?

Answer 9

The light intensity is inversely proportional to the square of the distance of the light from the plant

Question 10

Explain the effect of light intensity on the rate of photosynthesis

Answer 10

As light intensity increases, the rate of photosynthesis also increases up to a maximum level. This is because plants need light to photosynthesise
After this point , the rate levels off because another factor is limiting the rate of photosynthesis

Question 11

A student investigates the effect of light intensity on the rate of photosynthesis by counting the number of bubbles. Suggest one way the method could be improved to give valid results

Answer 11

Using a gas string to collect oxygen or using an oxygen sensor instead of counting bubbles released per minute

Question 12

Is photosynthesis an exothermic or endothermic process? Explain

Answer 12

Photosynthesis is endothermic because it stores energy from sunlight in glucose

Question 13

What is cellulose produced from glucose used for?

Answer 13

Strengthening cell walls

Question 14

How is the glucose produced during photosynthesis used to produced proteins?

Answer 14

Glucose is used to produce amino acids which are combined with nitrate ions to produce protein

Question 15

Explain the effect of amount of chlorophyll on the rate of photosynthesis

Answer 15

The more chlorophyll a leaf has, the more photosynthesis it can perform as it can absorb more energy

Question 16

When investigating the effect of light intensity on the rate of photosynthesis, name 2 control variables

Answer 16

Carbon dioxide concentration, temperature, species of pondweed, light source

Question 17

Give 4 factors that affect the rate of photosynthesis

Answer 17

Light intensity, temperature, carbon dioxide concentration and amount of chlorophyll