31 - Signals

Question 1

Tropism

Answer 1

Any response that causes the movement of plant organs toward or away from stimuli

Question 2

Types Tropism

Answer 2

Hydrotropism - water
Geotropisim - gravity
Phototropism - light
Thighmotropism - touch
Chemotropism - chemical signals

Question 3

Darwin Darwin
Boysen Jensen
Went

Answer 3

Tip of the plant response to light
Tip sends chemical signals to the stem
Auxin, the chemical responsible for moving the stem

Question 4

Auxin - phototropism

Answer 4

Sends signals down the stem, and it elongates cells away from the light, causing the plant to bend towards the light.

Question 5

Cytokinin

Answer 5

Determine root or shoot growth
More Cytokinin Shoot
More Auxin than Cytokinin Root

Question 6

Gibberellins

Answer 6

Induce elongation and cell division in stem
seed break dormancy

Question 7

Abscisic Acid

Answer 7

Stomata closure
Seed dormancy

Question 8

Ethylene

Answer 8

Ripening of fruit

Question 9

Signal transduction model

Answer 9

Light - external stimulus hits the receptor (photoreceptor blue light and photo chrome redlight)
Transduction - turns on gene expression
Response -The small molecule is produced Chlorophyll

Question 10

Germination Relationship with Red Light (PR) and Far Redlight PFR

Answer 10

Pr - in the inactive state and promotes germination - start
PFR - in the active state inhibits germination - stop (storage)

Question 11

Plants germinate based on dark time.

Answer 11

If critical fark time is less than dark time will not germinate.

Question 12

Mechanism of plant defense

Answer 12

Chemical - secrete itself in toxins
Physical - spikes, prods, thorns
Behavior / Signals - release hormones attracting preditors