P1 4.3.3 Plant disease (might come up)

Question 1

Signs of plant disease

Answer 1

stunted growth
spots on leaves
areas of decay (rot)
abnormal growths
malformed stems or leaves
discolouration
presence of pests

Question 2

What happens if plants have a nitrate deficiency

Answer 2

Stunted growth as nitrates are needed to make proteins which are needed for growth

Question 3

What happens if plants have a magnesium deficiency

Answer 3

Chlorosis and yellow leaves as magnesium ions are needed for chlorophyll which is needed for photosynthesis

Question 4

What are 3 plant physical defences

Answer 4

Waxy cuticle - barrier
Cell walls - barrier
Layers of dead cells around stem eg bark

Question 5

What insects attack plants

Answer 5

Aphids

Question 6

What are 2 chemical plant defences

Answer 6

Antibacterial chemicals eg witch hazel

Poisons to deter herbivores eg foxgloves

Question 7

What are 3 mechanical plant defences

Answer 7

Thorns and hairs
Leaves that droop or curl when touched
Mimicry to trick animals eg passion flower has bright yellow spots which look like butterfly eggs