4.5.4.2 Use of Plant Hormones Flashcards
1
Q
Why are plant hormones used to alter plant growth?
A
- increase yield
- obtain desirable features
- lower costs
2
Q
What are auxins used as?
A
- weed killers
- rooting powders
- for promoting growth in tissue culture
3
Q
Why are auxins used as weed killers?
A
- many weeds are broad- leaved
- weed killers containing auxin have been synthesised so they only affect broad-leaved plants
- increased amount of auxin causes rapid cell growth
- results in weed dying
4
Q
Why are auxins used as rooting powders?
A
- plants with desirable features are cloned to make more
- one way to do this is to take a cutting from original plant
- rooting powder applied to cutting and places in ground
- roots grow and new plant rapidly grows
5
Q
Why are auxins used to promote growth in tissue culture?
A
- cells from plants taken are placed in growth mediums containing many nutrients
- auxins are added
- cells begin to form roots and shoots
6
Q
How is ethene used in the food industry?
A
- fruit picked when not ripe
- firm meaning during transport it gets less bruised and damaged
- when needed to be sold, it is exposed to ethene and warmer temperature
- ethene involved in controlling cell division and stimulates enzymes that result in fruit ripening
- reduces wastage as more fruit is suitable
7
Q
What are gibberellins used for?
A
- ending seed dormancy
- promoting flowering
- increasing fruit size
8
Q
Why are gibberellins used for ending seed dormancy?
A
- in brewing industry, germination rate of barley seeds is increased to make malt
9
Q
Why are gibberellins used for promoting flowering?
A
- applying this hormone allows it to flower in any conditions with bigger flowers
10
Q
Why are gibberellins used for increasing fruit size?
A
- seeds in fruit produce gibberellins to increase fruit size
- means that seedless fruit is generally smaller
- seedless fruit can be sprayed with gibberellins to increase size
