Plant Growth and Development - 10-01-24

How many gibberellins have been reported from fungi and higher plants –

• (a) Less than 100

• (b) More than 1000

• (c) More than 100

• (d) 100

Which one(s) is acidic in nature?

• (a) Auxins

• (b) GAs

• (c) ABA

• (d) All

In coleoptile tissue, auxin –

• (a) Is not transported, because auxin is used where it is made

• (b) Is transported by diffusion, with no preferred direction

• (c) Is transported from base to tip

• (d) Is produced by the growing apices of the stem and roots, from where they migrate to the regions of their action

Which GA was the first Giberrellin to be discovered?

• (a) GA₁

• (b) GA₂

• (c) GA₃

• (d) GA₄

Gibberellins have many effects. Which one of the following is not an effect of gibberellins in plants?

• (a) Bolting

• (b) Delay senescence

• (c) Increase the grapes stalk

• (d) Induces dormancy

The fruits can be left on the tree longer so as to extend the market period. This is due to which function of GA?

• (a) Bolting

• (b) Delay senescence

• (c) Internodal elongation

• (d) Parthenocarpy

Which of the following hormones causes fruits like apple to elongate and improve its shape –

• (a) GA

• (b) ABA

• (c) NAA

• (d) 2, 4 D

Spraying sugarcane with gibberellins increases the yield by as much as 20 tonnes per acre. GA performs it –

• (a) By improving the quality of fruit

• (b) By making plants with rosette habit

• (c) By internodal elongation

• (d) By delaying senescence

Bolting is –

• (a) Internodal elongation just prior to flowering in beet, cabbage and many plants with rosette habit.

• (b) A type of grafting

• (c) Nodal elongation in certain plants

• (d) None

Which one is false?

• (a) GA₃ is used to speed up the malting process in brewing industry

• (b) Spraying juvenile conifers with GAs hastens the maturity, thus leading to early seed production

• (c) GA₃ is a commercially available gibberellin

• (d) GA₃ cannot increase the length of internode in sugarcane