Aggregation pheromones help in making a group of the animals of the same species. Gerdiol is an aggregation pheromone of honey bee.

When two hormones work together, then those hormones are known as synergesic hormones. For example, FSH and LH.

Correct answer. Hormones may be amino acids, amino acid derivatives, steroids, polypeptides or proteins, amines or glycoproteins. Hormones are non-antigenic, i.e. no antibody formation against hormones takes place.

Correct answer. Diethylstilbestrol is a synthetic nonsteroidal estrogen that was first synthesised in 1938. Fosfestrol is a synthetic estrogen used as an antineoplastic agent.

Correct answer. Cortisone, aldosterone and corticosterone all are secreted by adrenal cortex.

Correct answer. Pineal gland, hypothalamus and pituitary gland are endocrine glands.

All are natural plant growth hormones. Indole-3-acetic acid (IAA) is the most common, naturally-occurring, natural plant growth regulator hormone of the auxin class. Gibberellic acid (GA3) is an important natural plant growth regulator that is used commercially to increase plant growth and crop yields. Zeatin is a member of the plant growth regulator hormone family known as cytokinins.  

Follicle stimulating hormone (FSH), Luteotropic hormone (LTH) and Somatotropic hormone (STH) are all anterior pituitary hormones.

Human insulin is a polypeptide of 51 amino acids arranged in two chains (A and B) bearing 21 and 30 amino acids, respectively.

Correct answer. Chlorotrianisene is a non-steroidal synthetic estrogen that was formerly used for the treatment of menopause, deficiencies in the functioning of ovaries and prostate cancer. Diethylstilbestrol is a synthetic nonsteroidal estrogen that was first synthesised in 1938. Fosfestrol is a synthetic estrogen used as an antineoplastic agent.

This option is correct because ACTH consists of 39 amino acids.

Correct answer. 2,4-Dichlorophenoxyacetic acid (2,4-D) is a common systemic pesticide/herbicide used in the control of broadleaf weeds. It is one of the most widely used herbicides in the world and is the third most commonly used herbicide in North America. 2,4-D is a synthetic auxin (plant hormone). 2,4,5-Trichlorophenoxyacetic acid (2,4,5-T), a synthetic auxin, is a chlorophenoxy acetic acid herbicide used to defoliate broad-leafed plants.

Secretin is produced by intestinal mucosa and inhibits secretion of gastric juice. Melatonin is secreted by the pineal gland. Oxytocin is secreted from the posterior lobe of pituitary. Epinephrine is the hormone from medulla of the adrenal gland.

Correct answer. Cholecystokinin and pancreozymin are two hormones that stimulate the secretion of pancreatic juice. Cholecystokinin causes contraction of the gall bladder and discharges the bile into the duodenum. Pancreozymin also stimulates the pancreas to secrete insulin and glucagon.

Correct answer. Hypersecretion of melanophore stimulating hormone (MSH) causes hyperpigmentation. Hypersecretion of pancreotropic hormone (PTH) causes defects in pancreas. Hypersecretion of growth stimulating hormone (GSH) causes gigantism. Hypersecretion of thyrotrophic stimulating hormone (TSH) causes enlargement of thyroid.