Plant Growth and Development - Online Test
Q1. Exponential growth is dependent on
Answer : Option B
Explaination / Solution:
Exponential growth is dependent on initial size, rate of growth and time interval.
Q2. Which one is not a phase of Growth
Answer : Option D
Explaination / Solution:
Growth phase consists of leg phase, exponential phase and stable phase. It do not consist of linear phase.
Q3. The graphical representation of the total growth against time is called
Answer : Option B
Explaination / Solution:
A growth curve is an empirical model of the evolution of a quantity over time or a graphical representation of how a particular quantity increases over time.
Growth curves are used in statistics to determine the type of growth pattern of the quantity - be it linear, exponential or cubic.
It is also known as Sigmoid curve.
Q4.
If is the final size, is initial size, r is growth rate and t is time of growth than Exponential growth is represented by
Answer : Option A
Explaination / Solution:
Exponential growth is represented by initial size and growth rate and time. If is the final size, is the initial size, r is growth rate and t is the time of growth than exponential growth is
Q5. Natural cytokinins are synthesized in
Answer : Option A
Explaination / Solution:
Natural cytokinins are synthesised in regions where rapid cell division occurs, for example, root apices.
Q6. Which one prevents premature fall of fruit?
Answer : Option A
Explaination / Solution:
They help to prevent fruit and leaf drop at early stages but promote the abscission of older mature leaves and fruits.
Q7. Which hormone is responsible for dormancy?
Answer : Option A
Explaination / Solution:
Abscistic acid encourages fruit to drop and leaves to fall. When the plant is low on water abscistic acid closes the stomata, pores in the leaves. It encourages both seeds and plants to go dormant.The hormone induces seeds to produce proteins to store when the seeds are dormant.
Q8. Auxin was isolated from tips of coloeptile of oat seedlings by
Answer : Option A
Explaination / Solution:
Auxin was first collected by F.W. Went (1928) from coleoptile tip of Avena. He also developed Avena curvature test for bioassay of auxin.
Q9. Auxins are mostly produced in
Answer : Option C
Explaination / Solution:
Auxins are generally produced in growing apices of shoot and root. These two regions are the meristematic cells which are actively taken part in cell division.
Q10. Natural auxins among the following are: a) IAA, b) IBA, c) NAA and d) 2, 4 D
Answer : Option D
Explaination / Solution:
Auxins like IAA and indole butyric acid (IBA) have been isolated from plants.(naturally) NAA (naphthalene acetic acid) and 2, 4-D (2, 4-dichlorophenoxyacetic)are synthetic auxins.
