SL Plants

Question 1

what does flowering involve?

Answer 1

• when there is a change in expression at a shoot apex and leaves turn into flowers
• can be triggered by temperature but most often by length of fay (light and dark periods)

Question 2

what is the role of phytochrome?

Answer 2

• they are interchangeable pigments in the form of Pr and Pfr
• Pr absorbs red light (during day) and converts to Pfr
• Pfr absorbs far red light @ night and converts to Pr again
• Pfr accumulates during day, and if short night (summer), not all Pfr with convert back to Pr triggering long day flowers
• if long night, all Pfr converts to Pr triggering short day flowers

Question 3

what kind of relationship do plants use for pollination?

Answer 3

• mutualistic relationship with pollinator in sexual reproduction
• pollinators are 85% animals: mostly bees, moths, birds, bats
• other 15% is dispersal through water + wind

Question 4

what is pollinization?

Answer 4

• transfer of pollen from stigma to another on other plant
• pollen germinates on stigma, and a pollen tube grows down style to ovary

Question 5

what is fertilization in plants?

Answer 5

when make gametes fuse with ovule to make zygote

Question 6

what is seed dispersal? give examples

Answer 6

• dormant seed dispersed to reduce competition with parent
• methods: explosive, fruits attracting animals, burs attach to fur

Question 7

what is needed to germinate a seed?

Answer 7

• oxygen, water, warm temp
• NOT light or CO2

Question 8

what is the role of giberellin?

Answer 8

• growth hormone produced by cotyledon after rehydration
• promotes production of amylase, which catalyzes digestion of starch into maltose (maltose to glucose for energy)

Question 9

provide differences between monocots and dicots

Answer 9

Monocots
- one cotyledon
- parallel leaf veins
- fibrous roots
- petals in multiples of 3
Ex: tulip, bamboo, corn

Dicots
- two cotyledons
- netlike leaf nein
- usually taproots
- petals in multiples of 4 or 5
Ex: tomato, bean, sunflower