Introduction of Plant Hormones
Plant hormones are also known as phytohormones. Plant hormones can be described as chemical substances produced in plants that may be transmitted from one region to another and regulate one or more physiological reactions while present in low concentrations. Some of the important plant hormones are – Auxin, Gibberellin, Ethylene, Abscisic acid, and Cytokinin. These hormones are involved in growth and development responses such as cell division, seed formation, flowering, seed formation and abscission.
MCQs on Plant Hormones
Let us learn some information about the planet hormones in the form of multiple choice questions here.
1. Indole-3-acetic acid is the most known and naturally occurring plant hormone of _______ class.
(a) Gibberellin
(b) Auxin
(c) Ethylene
(d) Cytokinin
Ans: Auxin
2. Which of the following hormones is not a growth inhibitor?
(a) Dormin
(b) Abscisic acid
(c) Ethylene
(d) IAA
Ans: IAA
3. ___________ is a gaseous plant hormone.
(a) IBA
(b) Ethylene
(c) Abscisic acid
(d) NAA
Ans: Ethylene
4. A widely used rooting hormone is
(a) 2,4, -D
(b) NAA
(c) 2,4,5 – T
(d) Cytokinin
Ans: NAA
5. The leaf defoliator utilized as “Agent Orange” was
(a) 2,4, -D and 2,4,5 – T
(b) Ethylene
(c) 2,4, -D and NAA
(d) 2,4,5 – T, ethylene and NAA
Ans: 2,4, -D and 2,4,5 – T
6. Transport of auxin is
(a) non-polar
(b) symplast
(c) apoplast
(d) solar
Ans: polar
7. Formation of the nodule is induced by
(a) IAA
(b) NAA
(c) IBA
(d) Both (a) and (c)
Ans: IAA
8. __________is the precursor of Indole-3-acetic acid.
(a) Methionine
(b) Tryptophan
(c) Glycine
(d) Isopentenyl pyrophosphate
Ans: Tryptophan
9. This bioassay that is used to detect the presence of auxin is/are
(a) Only tobacco pith culture
(b) Tobacco pith culture and Avena curvature test
(c) A curvature test related to Tobacco pith culture and Split pea stem
(d) Tests related to Split pea stem curvature and Avena curvature
Ans: Split pea stem curvature test and Avena curvature test
10. Which of these is not a function of auxin?
(a) Inducing callus formation
(b) Inducing dormancy
(c) Enhancing cell division
(d) Maintaining apical dominant
Ans: Inducing dormancy.
FAQs on MCQs on Plant Hormones
1. Why is abscisic acid also known as stress hormone?
Abscisic acid is known as a stress hormone as its production is stimulated by drought, water logging and other adverse conditions. This hormone induces dormancy of buds and it also promotes seed dormancy.
2. State two functions of ethylene.
Two functions of ethylene are given below:
Ethylene promotes apical dominance and prolonged dormancy of lateral buds.
It helps in the ripening of the climacteric fruits.
3. Name two synthetic auxins.
Two of the important synthetic auxins are- IBA (Indole 3-butyric Acid) and NAA(Naphthalene acetic acid).
