Nutrition in Plants

Question 1

Oxygen + Glucose

Answer 1

Carbon dioxide + Water in the presence of light

Question 2

Factors limiting rate of photosynthesis

Answer 2

Light intensity, carbon dioxide concentration (normally) and temperature (enzymes can denature)

Question 3

Cuticle

Answer 3

Reduces water loss by evaporation and acts as a barrier to the entry of disease-causing microorganisms

Question 4

Upper epidermis

Answer 4

Relatively transparent to allow light to pass through

Question 5

Palisade mesophyll

Answer 5

Long, narrow cells containing hundreds of chloroplasts, close to the source of light and main site of photosynthesis

Question 6

Spongy mesophyll

Answer 6

Still photosynthesises though with fewer chloroplasts, they form the main gas exchange surface

Question 7

Air space

Answer 7

Allows gases to diffuse in and out

Question 8

Use of nitrate

Answer 8

Making amino acids, proteins, chlorophyll, DNA and other compounds

Question 9

Nitrate deficiency symptoms

Answer 9

Limited growth of plant; Older leaves turn yellow

Question 10

Use of phosphate

Answer 10

• Making DNA and other compounds
• Part of cell membranes

Question 11

Phosphate deficiency symptoms

Answer 11

Poor root growth; Younger leaves turn purple

Question 12

Use of potassium

Answer 12

Needed for enzymes for respiration and photosynthesis to work

Question 13

Potassium deficiency symptoms

Answer 13

Leaves turn yellow with dead spots

Question 14

Use of magnesium

Answer 14

Part of chlorophyll molecule

Question 15

Magnesium deficiency symptoms

Answer 15

Leaves turn yellow

Question 16

Describe an experiment to measure the effects of limiting factors upon photosynthesis

Answer 16

1. Remove leaf
2. Dewax in boiling water for 30s
3. Remove colour in boiling ethanol (turn off Bunsen burner)
4. Wash with cold water
5. Test by adding iodine solution
6. Vary limiting factor (use bell jar containing soda lime to remove carbon dioxide) and repeat