Plant
Hormones
Created by Rachel Nolen and Josie Colaneri
for AP Biology
Background Information (Auxin)
- Auxin was the first plant hormone to be discovered.
- Found in the embryo of the seed, meristems on apical buds and young leaves
- Found in high and low concentration
Background Info
Background Information (Gibberellins)
Gibberellins
- Gibberellins are found in the meristems of apical buds/roots and in young leaves
- Plants in their normal state will produce a large amount of gibberelins
- Made in exposure to blue light
Background Information (Ethylene)
- Ethylene is a gas
- It is produced in responce to stress
- Often opposes affects of auxin
- It is found in most parts of plants
Ethylene
Affects of Auxin
- Acid Growth Hypothesis - increases wall plasticity and allows for the cell walls to elongate and the plant to grow
- Stimulates cell (shoot) elongation in low concentrations
- Inhibits cell elongation in high concentrations
- production of ethylene inhibits growth
- Phototropism-
- Will move to the shaded side of a plant to allow the plant to grow toward the sunlight
Affects
Affects of Gibberellins
- Works in developing seeds
- seed and bud germination
- pollen development and tube growth
- sex determinant
- fruit development
- stem elongation
- leaf growth
- Controls the cycle of plant growth, especially flowering
Affects of Ethylene
- Mainly produces fruit ripening when the gas is exposed to unrip fruits, they will ripen faster
- Leaf Abscission - breaks down the chlorophyll in leaves, reason for the different colors in transition of summer to fall
- Helps with apoptosis
Affects of Ethylene
Who Would Use Auxin?
Uses
- Florists can use auxin to promote growth of their flowers and plants
- Willl help with stem elongation and the beautification process.
Who Would Use Gibberellins?
- Gibberelins would be used by farmers to enhance the appeal of their foods.
- They make fruits grow faster such as grapes and it makes the grapes larger and juicer.
Who Would Use Ethylene?
- Ethylene would be removed by transporters of fruits to keep them from ripening during transport. After arrival the hormone would be reintroduced so the fruits will all ripen at the same time.
Slogans
Slogans
- Why be short and stubby, when you could be tall and shrubby... with auxin!!
- Great Gibberelins Generate Greenery
- Make your fruits ripe and green, with the help of ethylene