Chapter 31 Flashcards
What are Growth of plants are influenced by?
1) Genetic factors
2) External environment factors
3) chemicals
What are growth hormones in plants?
Chemical messengers that affect a plant’s ability to respond to its environment.
What are auxins?
A hormone in plants that elongates a plant.
What are Examples of auxins?
Indolaestic acid (IAA)
Naphthalene acetic acid (NAA)
What does NAA do if used in the right time?
When NAA is sprayed on young fruits, some of the fruits would drop so the remaining fruits grow larger.
NAA is also used to prevent buds from sprouting.
What does NAA do when used in the wrong time?
NAA prevents fruits from dropping of the trees.
What are gibberellins?
A hormone in plants that increases the size, and if extracted and sprayed, it may cause them to grow larger.
What is Ethylene?
A gas at room temperature and diffuses easily from plant to plant causing them to ripen and rot quicker.
What can ethylene be used for?
Abscission, detaching leaves, flowers, and fruits, this can prevent them from taking up nutrients and getting diseased.
What are cytokinins?
Promotes cell division in plants also used to promote lateral bud growth of flower crops.
Explain cytokinins ratio with auxins.
At high ratios of auxin-to-cytokinins stimulate root formation.
At low ratio promotes shoot formation.
What is Abscisic acid?
Helps bring dominancy in plants bud and seeds.
It also causes the stomata to close in response to drought.
What are growth retardants?
Prevents plant growth, which is also useful to prevent interference with other things in the environment.
What are the two classifications for plant movement?
Tropism which is directional response to stimuli.
Nastic which is non-directional response to stimuli.
What is positive tropism?
Growth towards an environmental stimulus.
