Controls of plant growth

Question 1

types of plant hormones

Answer 1

• auxins
• gibberellins
• abscisic acid
• cytokinins
• ethene

Question 2

what is the purpose of synthetic auxins?

Answer 2

herbicides

Question 3

where is the sites of auxins production?

a. shoot apical meristems / shoot buds and root tips
b. lateral meristems
c. young leaves
d. seeds
e. fruit

Answer 3

a,c,d

Question 4

what is the role / principal actions of Indoleacetic acid (IAA)?

a. stem elongation
b. root initiation
c. flowering
d. fruit development
e. apical dominance
f. embryo development
g. response to gravity and light

Answer 4

a,b,d,e,g

Question 5

effect of auxin to the shoot tip and stem?

Answer 5

a. decreased cell division

b. increased elongation

Question 6

gibberellin produces at ?

a. young leaves
b. embryo in seed
c. root tips
d. chloroplasts

Answer 6

all of the above

Question 7

principal actions of gibberellin?

Answer 7

• seed germination / seeds break dormancy
• stem elongation
• flowering
• fruit development

Question 8

which hormones needed by the growers to enhance stem length and control ripening?

a. auxins
b. abscisic acid
c. gibberelins

Answer 8

c

Question 9

1. where cytokinins is produced in mature plants?

2. location cytokinins is exported from roots?

Answer 9

1. roots

2. seeds, fruits, shoots

Question 10

cytokinins most abundant at?

a. young leaves
b. root and shoot meristems
c. seed embryo

Answer 10

b

Question 11

how to extend the shelf life of cut flowers?

Answer 11

use cytokinins

Question 12

principal actions of cytokinins

a. seed germination
b. stem elongation
c. flower development
d. embryo development
e. cell division
f. delay of leaf death
g. inhibition of apical dominance

Answer 12

all of the above

Question 13

what is the effect of cytokinins to the seed?

Answer 13

initiates germination

Question 14

abscisic acid cause?

Answer 14

• suspension of growth

- promotes dormancy of buds and seeds

Question 15

dormancy in plants to be shipped is induced by?

Answer 15

abscisic acid

Question 16

what is the effect of abscisic acid to the plant?

a. decreased cell elongation
b. promotes leaf and fruit abscission
c. induces flowering
d. stoma close in drought condition
e. stem elongation

Answer 16

a, b, d

Question 17

ethylene promotes?

Answer 17

ripening of fruit

Question 18

arrange the basic mechanism of action in plant hormone:

a. hormone bind to specific receptor proteins of the plasma membrane
b. ions Ca2+ serve as second messengers
c. once the concentration of Ca2+ / second messenger increases in cell, it bind to proteins and activate protein kinase
d. the binding activates a G protein in the plasma membrane.
e. the enzyme alter cell activity

Answer 18

a, d, b, c, e