Plant Hormones Flashcards
What are auxins
plant hormones that control growth at the shoots and roots of the plant by being dissolved
what does auxins do in the roots and shoots
in the shoot it promotes growth and in the root it inhibits growth
are shoots positively or negativity phototropic
shoots are positively phototrophic because when shoot is exposed to light the shaded side is more concentrated with auxins causing it to elongate faster and bend towards the light
why is bending to the light beneficial for the plants and what does it mean if they dont have access to light
- because they can absorb more light for photosynthesis enabling cell growth
- however not being surrounded w light causes it to grow tall as auxins make them to elongate on all sides which allow better chance for finding light
are shoots negatively or positively gravitropic
negatively gravitropic because gravity accumulate on lower side cause grow faster and grow upwards
are roots positively or negatively phototrophic
negatively phototrophic because root growing sideways have auxins on lower side and this extra auxins inhibit cell growth causing top to elongate faster and root bend downwards
Identify the three plant hormones used for commercial uses
auxines , gibberellins , ethene
what are the commercial uses of auxins
selective weedkillers and rooting powder
what do weedkillers do
many weeds such as broad leaved plants are unwanted so selective weedkillers are developed to disrupt the growth of the crops and kill them
what are rooting powders
cutting of plants taken off and placed in soil w rooting powder to produce roots and grow as plants this produces clones of the good plant
What is the commercial use of ethene
used to delay food ripening of fruit during storage or transport to allow it to be unripe whilst in transport and so less damaged so when required to be on shelves can be added to be perfect for sales
What is the commercial uses of gibberellin
seed germination
producing seedless fruit
flowering formation
what is seed germination
when the plant cannot germinate due to certain conditions not being met so seeds treated with gibberellins to germinate at times of year that wouldn’t normally and at same time
what is producing seedless fruit
fruit with seeds in the middle only grows on flowering plants that have been pollinated. If gibberellins are applied to the unpollinated flowers of some plants, the fruit grows but no seeds develop within it
what is fruit formation and flower formation
allowing plants and fruits to germinate in periods of time or conditions that wouldn’t usually flower
- reduce flower formation which improve fruit quality for example some fruits are formed a-lot but very small so fewer fruits being formed but larger and nicer is beneficial
