Plant responseszs Flashcards
1
Q
What a tropisms?
A
environmental cues, e,g. light and water
2
Q
What are the limitations of plants compared to animals?
A
- unable toi move
- no nervous system
- therefore timescales are slowed
3
Q
What are the roles of auxins?
A
- control cell elongation
- prevent abscission (leaf fall)
- maintain apical dominance
- stimulate release of ethene
- involved in fruit ripening
4
Q
What are the roles of gibberelin?>
A
- stem elongation
- mobilisation of food stores in a seed at germination
- stimulate pollen tube growth in fertilisation
5
Q
What is the role of ethene?
A
- causes fruit ripening
- promotes abscission in deciduous tress
6
Q
What is ABA?
A
abscisic acid
7
Q
What is the role of ABA?
A
- maintains dormancy of seeds and buds
- stimulates cold protective response
- e.g. antifreeze production
- stimulates stomatal closure
8
Q
Why are the details of plant responses low?
A
- plant hormones work at very low concentrations
- so isolating them and measuring changes in conc is not easy
- multiple interactions between the different chemical control systems also makes it difficult to isolate the role of a single chemical
