Functions Of Hormones

Question 1

Define hormones

Answer 1

Hormones in general are signaling molecules which are produced in small quantities, get transported from the place they are produced to other parts of the organism and trigger responses in target cells. or/and effect on plant growth and development.

Question 2

Define plant growth regulators

Answer 2

Plant growth regulators are natural or synthetic organic compounds which modify or control specific physiological process in plants.

Question 3

State 3 major types of plant hormones

Answer 3

auxins, gibberlin, cytokinin, abscisic acid, ethylene and Jasmonate (jasmonic acid).

Question 4

How do plant hormones ( signaling molecules in plants) differ from hormones general

Answer 4

Plants hormones act locally , whereas hormones in general are produced at one site and transported to other parts of the organisms where it is required.

Activated even at very low concentrations

Question 5

Auxin

Answer 5

stimulates stem elongation in low concentration
• promotes the formation of lateral and adventitious roots
• regulates development of fruit
• enhances apical dominance
• functions in phototropism
• functions in gavitotropism
• promotes vascular differentiation
• retards leaf abscission

Question 6

Gibberellins

Answer 6

• stimulate stem elongation
• stimulate pollen development
• stimulate pollen tube growth
• stimulate fruit growth
• stimulate seed development and germination
• regulate sex determination and transition from juvenile to adult phase

Question 7

Cytokinins

Answer 7

• regulate cell division in shoots and roots
• modify apical dominance and promote lateral bud growth
• promote movement of nutrients into sink tissues
• stimulate seed germination
• delay leaf senescence

Question 8

Abscisic acid

Answer 8

• inhibits growth
• promotes stomatalclousure during drought stress
• promotes seed dormancy and inhibits early germination
• promotes leaf senescence
• promote dessication tolerance

Question 9

Ethylene

Answer 9

• promotes ripening of many types of fruit
• promote leaf abscission
• promote triple response in seedlings (inhibition of stem elongation, promotion of lateral expansion, and horizontal growth)
• enhance the rate of senescence
• promote roots and root hair formation
• promotes flowering in the pineapple family

Question 10

What are the triple response in in seeding

Answer 10

inhibition of stem elongation
promotion of lateral expansion
horizontal growth