Question

Match the following and find the correct combination

I	II
a) Auxin	$1$. Herring of sperms
b) Cytokinin	$2$. Inhibitor of growth
c) Gibberellin	$3$. Apical dominance
d) Ethylene	$4$. Epinasty
e) Abscisic acid	$5$. Induces amylase synthetase

Answer 1

Plant growth regulators are small, simple molecules of different chemical compositions that can regulate growth in plants. Some examples are auxin, cytokinin, gibberellin, ethylene, and abscisic acid.

Complete answer:
Plant growth regulators regulate growth in plants. Some examples are auxin, cytokinin, gibberellin, ethylene, and abscisic acid.
Auxin- They have an unsaturated ring structure that is weakly acidic. They promote the elongation of cells in the shoot. It can work at a very less concentration of $10$ ppm to inhibit the root elongation. It also has a function of Apical Dominance.
Cytokinin- It promotes the cytokinesis of cells during cell division and is weakly basic.
Gibberellin- It is generally involved in the cell elongation of intact plants and also increases the length of genetically dwarf plants.
Ethylene- It is a gaseous hormone that promotes diametrical growth and retards longitudinal growth. It is a fruit ripening hormone used for the assay of colouring in lemons.
Abscisic acid- It inhibits the shoot growth but has nothing to do with root effects. It acts as an antagonist of Gibberellin.

a) Auxin-	$3$. Apical dominance
b) Cytokinin-	$1$. Herring of sperms
c) Gibberellin-	$5$. Induces amylase synthetase.
d) Ethylene-	$4$. Epinasty
e) Abscisic acid-	$2$. Inhibitor of growth

Therefore, this is the correct match to the following growth regulators.

Note:
A plant hormone is a chemical substance that can be translocated to another region for the regulation of growth when present in low concentrations. Plant growth regulators may either be plant growth promoters or plant growth inhibitors, depending upon their function.