4 The importance of water and minerals in plants

Question 1

why do plants need water? (4)

Answer 1

• photosynthesis
• support
• transport
• to keep cool

Question 2

Why do plants need nitrates? (2)

Answer 2

• they are used to make amino acids and therefore proteins, including plant enzymes without which the the cells could not function
• nitrates needed to make DNA and hormones

Question 3

what happens when a plant is lacking nitrates? (3)

Answer 3

• the older leaves turn yellow and die
• growth is stunted
• eventually plant dies

Question 4

why do plants need calcium? (2)

Answer 4

• in middle lamella calcium ios combine with pectin to make calcium epctate which holds plant cells together
• important in the permeability of membranes

Question 5

what happens when plants lack calcium?

Answer 5

• the growing points die back and yound leaves are yellow and crinkly

Question 6

why do plants need magnesium? (2)

Answer 6

• needed to produce the green pigment chlorophyll

- also needed for the activation of some plant enzymes

Question 7

what happens when plants lack magnesium? (2)

Answer 7

• if plants do not have enough magnesium and therefore not enough chlorophyll, they will eventually die
• yellow areas develop on the older leaves and growth slows down