Plant Hormones Flashcards
(9 cards)
1
Q
What are the 5 plant hormones?
A
- Gibberellin
- Abscisic acid
- Auxin
- Ethylene
- Cytokinin
2
Q
Gibberellin
A
- determines when seeds will germinate
- fruit development
- elongates stem internodes
3
Q
Abscisic acid
A
signals dehydration, making leaves close their stomata (openings) to prevent water loss through transpiration.
4
Q
What is transpiration?
A
The evaporation of excess water from the stomata
- helps with upward movement of water in the plant
- helps with regulating plant’s temperature
5
Q
Auxin
A
Hormone synthesised at stem tips:
- travels downwards
- moves to shaded areas of the plant
- causes phototropism/makes plant bend towards the light source
6
Q
Ethylene
A
- in the form of gas
- ripens fruit
- stimulates senescence (leaves falling off)
7
Q
Cytokinin
A
- produced at root tips
- prevents senescence
8
Q
Which two hormones work together to determine whether a plant should grow roots or shoots?
A
Cytokinin (promotes roots)
and
Auxin (promotes shoots)
9
Q
What are the 5 stimuli that plants respond to?
A
Gravity (geotropism)
Light (phototropism)
Temperature (Thermotropism)
Touch (Thigmotropism)
Moisture (Hydrotropism)
