Chapter 22.3, Problem 1MI

Summary Introduction

To compare:

The four plant hormones and complete the table.

Introduction:

There are many plant hormones, such as, auxin, ethylene, abscisic acid, cytokinins, gibberellins, and salicylic acid. The functioning of plant under stress is maintained by plant hormone. These hormones help plant to survive under environmental stress.

Explanation of Solution

The information about four plant hormones is completed as shown below:

Hormone	How this hormone regulates growth	Characteristic of this hormone	Another benefit of this hormone
Auxin	This hormone is found in stem tip to promote cell elongation. It acts in the darker side of the plant and allow that side to grow.	There are five types of auxins that are found in the plant. It contains the indole ring in it.	Inhibiting growth of lateral buds and maintaining apical dominance.
Gibberellin	This hormone induce rapid root and stem growth, allow cell division, and increase the rate of seed germination.	Promotes flower stem and shoot lengthening in the dark. This hormone reverses the effect of ABA.	It also helps in flowering and fruit patterning.
Cytokinin	By allowing cell division, this hormone regulates the size of short meristem, size of leaf and shoot as well.	It induces cell broadening, leaf formation, root differentiation, and new shoot formation.	Cytokinin mediates axillary bud release with apical dominance.
Ethylene	This hormone inhibits or promotes plant growth depending on its concentration, application time, and species of plant.	It is a colorless gas and has sweet smell and odor.	It regulates senescence apart from growth.