6.1.1 Survival + Response Flashcards
1
Q
Describe and explain the positivly phototrophic response of plants
A
- Shoot tip produces IAA
- IAA diffuses down shoot
- IAA accumulates on shaded side of plant
- Causing more elongation of cells on shaded side
- Shoot bends towards the light
2
Q
Describe and explain the positive gravotropic response of plants
A
- Root tip produces IAA
- IAA diffuses down root
- IAA accumulates on lower side
- IAA inhibits cell elongation in roots, causing less elongation of cells on lower side
- Shoot bends downwards
3
Q
What is a taxis
A
Directional response
4
Q
What is a kinesis
A
Non-direction, random response
5
Q
What is the prefix before a taxis
A
positive or negative AND type of taxis (chemotaxis, phototaxic etc.)
6
Q
What classifies a system as a reflex arc
A
Only involves three neurones, and doens’t involve the brain
7
Q
Why are reflex arc’s advantageous
A
- Rapid
- Doesn’t have to be learnt
- Protects damage to body tissue
