Plant Hormones Flashcards
Multiple Choice
- positive gravitrophism
Explain how this change in root growth has occurred
- Auxin moves to the underside of the plant
- inhibits elongation of the root cells (on underside)
- cells on upper side continue to elongate making root grow downwards
Suggest advantages to the plant of this response
- make the plant stable
- so root can reach water
Suggest why Rebecca and Andy set up a control experiment
- to see what the shoot would do in normal conditions
Explain the results of Rebecca’s and Andy’s experiment
- Rebecca’s shoot didn’t curve, Andrew’s did
- Rebeccas didn’t let light to shine on the top because of the cap
- so the auxin is evenly distributed
- andrews experiment, the jelly allowed auxin to move to the shaded side
- causing cell elongation
Multiple Choice
CBA
multiple choice
D - positive phototropism
State the plant hormone that causes the cress to grow towards the light
- auxin
Describe a method the student could use to show that the hormone was found in the tip of the plant shoot
- remove tip from one of the plant shoots and leave the other
- measure changes in growth and direction of movement
Explain why the waxy cuticle is important for this pine leaf
- surround the pine leaf
- so prevents water loss from the pine leaf
Which row is correct for the movement of sucrose through the plant?
D - Translocation and Phloem
Explain how the auxins cause the shoot of a plant to grow towards the light.
- auxins move to the shaded side of shoot
- causing cells on shaded side to elongate
Describe the effect of ethylene on the ripening of bananas
- as ethane concentration rises, there is an increase in the % of bananas that ripen
Explain which concentration of ethylene a supermarket should use to be the most cost effective when ripening bananas
- 3% concentration should be used
- would be too expensive to increase above 3%
- no added benefits past 3%
- below 3%, not all bananas ripen
Fruit ripening is one of the uses of plant hormones. Describe other uses of plant hormones in crop production.
SELECTIVE WEEDKILLERS (auxins or gibberellins)
- allow broad leaves plants to grow uncontrollably and die
- narrow leave plants and crops stay unaffected and survive
ROOTING POWDERS (auxins)
- plant cuttings are dipped in rooting powders
- roots develop rapidly
- large number of plants can be produced from the same plant
- no need to wait for the plants to grow from a seed
SEEDLESS FRUIT PRODUCTION (gibberellins)
- fruit will develop but the seeds inside will not
- larger biomass
