Which of the following is a plant hormone?

(a) Insulin
(b) Thyroxin
(c) Oestrogen
(d) Cytokinin.

AcademicBiologyNCERTClass 10

Correct Answer: (d) Cytokinin.

Plant hormones are the chemicals or hormones that perform the function of control and coordination in plants. Plant hormones are responsible for the following:

(i) Growth of stem: Gibberellins

(ii) Promotion of cell division: Cytokinin

(iii) Inhibition of growth: Abscisic Acid

(iv) Elongation of cells: Auxin.

Hormones are chemical substances that act like messenger molecules in the body of multicellular organisms. After being made in one part of the body, they travel to other parts of the body where they help control how cells and organs do their work.

Some important hormones in a human body are:

(a) Thyroxine-Thyroxine is a hormone, produced by the thyroid gland which stimulates the metabolic rate.  It controls the speed at which oxygen and food products react to release energy for the body to use.

(b) Insulin - Insulin is a hormone released from the pancreas into the bloodstream so that it can reach different parts of the body and regulate the blood sugar (glucose) level in the body.

(c) Adrenaline - The adrenaline hormone is released by the adrenal gland, which is located on top of the kidney. It prepares our body to function at maximum efficiency in emergency situations, like anger danger, stress, etc. Hence, it is called an emergency hormone. The function of the adrenaline hormone is to regulate the heartbeat, breathing rate, blood pressure, and carbohydrate metabolism.

(d) Growth hormone - Growth Hormone (GH) is responsible for the growth and development of humans. Less secretion of GH results in dwarfism.

(e) Testosterone - Testosterone is the male sex hormone secreted by the testes and responsible for male puberty and other secondary sexual characteristics.

Updated on 10-Oct-2022 13:19:02