Hormones (Quiz 3)

Question 1

hormones do not necessarily _____ _______, they ______ _______

Answer 1

“cause” changes, they singal changes

Question 2

small concentrations of hormones lead to

Answer 2

huge responses

Question 3

signal receptors may be

Answer 3

proteins in the cell membrane or cytoplasm

Question 4

what likely has receptors in the cytoplasm?

Answer 4

uncharged or nonpolar signals

Question 5

where are hormones made?

this leads to

Answer 5

unlike animals, plant hormones can be produced where they are needed (some exceptions)
this leads to redundancy in plants

Question 6

hormone transport: (3)

Answer 6

X (produced near root)
P (produced near root)
Polar (parenchyma cell to parenchyma cell)

Question 7

important hormones: (5)

Answer 7

1. ) auxins
2. ) cytokinins
3. ) ethylene gas
4. ) abscisic acid (aba)
5. ) gibberellins

Question 8

Auxins are perhaps

Answer 8

the most important group of hormones in land plants

Question 9

Auxins can be synthesized by

Answer 9

all land plants except liverworts (most basal group)

Question 10

most common Auxin =

Answer 10

indole acetic acid (IAA)

Question 11

Auxins are typically synthesized in (location)

Answer 11

shoot apical meristems & young leaves

Question 12

Auxins are transported: (2)

Answer 12

1. ) basipetally = from apical meristems to plant base (polarly)
2. ) acropetally = from the base of the plant to the apical meristems via the phloem

Question 13

auxins signal for: (6)

Answer 13

1. ) apical dominance –> axillary buds suppressed
2. ) phyllotaxy –> responsible for sites on leaf initiation in the apical meristems
3. ) growth in shoot cells
4. ) can retard growth in root cells
5. ) root production (tissue culture)
6. ) vascular tissue differentiation

Question 14

Auxins determine

Answer 14

leaf arrangement

Question 15

Cytokinins singal for

Answer 15

cell division/shoot growth

Question 16

Cytokinins are only in

Answer 16

angiosperms

Question 17

Most common Cytokinin

Answer 17

zeatin

Question 18

Cytokinins are primarily synthesized near

Answer 18

root apices

Question 19

Cytokinins primarily transported

Answer 19

in the X

Question 20

Auxin : cytokinin ratio affects

Answer 20

shoot & root development

Question 21

Cytokinins can delay

Answer 21

leaf senescence

Question 22

Ethylene Gas is a

Answer 22

simple hydrocarbon

Question 23

Ethylene Gas is likely the

Answer 23

first hormone recognized

Question 24

Ethylene Gas signals for: (5)

Answer 24

1. ) Defoliation –> used to be used in street lamps (therefore trees lost leaves)
2. ) Fruit Ripening (bananas)
3. ) Inhibition of cell expansion (except in aquatic plants they signal growth)
4. ) Abscission of fruits & leaves –> layer of dead cells allowing separation of organs (ex: at base of branch)
5. ) Senescence –> show decrease in physiological activity & t.f. death ):

Question 25

Abscisic Acid aka

Answer 25

ABA

Question 26

Abscisic Acid (ABA) signals for: (2)

Answer 26

1. ) dormancy —> seeds (ABA is either leached &/or signal for other hormone production) (w/ cue = light, water, temp)
2. ) stomatal closure (drought)

Question 27

Abscisic Acid (ABA) likely does not signal for

Answer 27

abscission

Question 28

Abscisic Acid (ABA) is transported through

Answer 28

phloem and xylem

Question 29

Gibberellins are made

Answer 29

where they are needed

Question 30

Gibberellins are key in

Answer 30

seed germination & seedling growth

Question 31

Gibberellins signal for: (5)

Answer 31

1. ) breaking seed dormancy
2. ) stimulate germination & seedling growth
3. ) cause bolting (production of inflourescence) (ex: cabbage, lettuce, agaves)
4. ) causes tall growth in short/dwarf plants to make them normal
5. ) “foolish seedling disease”

Question 32

Gibberellins are located throughout

Answer 32

the whole plant and may be made in all plants

Question 33

lodging =

Answer 33

shoots fall over because they are weak