 New students, in this topic we shall discuss, simulate and tabularize all the hormones which are involved in metabolism and development. Several hormones that we have studied so far are involved in the regulation of metabolism and developmental processes. These hormones include insulin, glucagon, glucocorticoids, catecholamines, thyroxine and growth hormone. These hormones are secreted by different endocrine glands and belong to different chemical categories i.e. they may be proteins, steroids or amines. But all have their role in metabolism and development. We shall summarize them first in insulin which is produced by the beta cells of pancreas. It is a protein hormone and it targets almost all tissues of the body except the neural tissues. Its primary action is to increase the uptake of glucose and amino acids by the cells. This hormone is more secreted in the high plasma glucose and amino acid levels while its secretion decreases in the low glucose levels as a result of which its secretion inhibits smetostatin hormone. Glucogon hormone which is produced by the alpha cells of pancreas is a protein hormone. Its target tissues are the liver and adipose tissues. Its primary action is to stimulate glycogenolysis. It also promotes lipolysis and in the adipose tissues. Glucogon secretion increases when glucose levels are reduced in the blood. In addition to this, somatostatin hormone inhibits its production. Glucocorticoids in which cortisol, cortisone and corticosterone are produced by the adenyl cortex and these three are steroid hormones. Their target tissues are liver and adipose tissues. Their primary actions are to mobilize amino acids from muscles and fatty acids from adipose tissue. They stimulate gluconeogenesis by liver and as a result they raise the blood-glucose level. They also exhibit anti-inflammatory actions. Their secretion is increased during stress and their secretion is regulated by negative feedback through the CRH and ACTH from hypothalamus and pituitary. Also their secretion is regulated by a biological clock. The catecholamines have also important role in metabolism. The epinephrine and norepinephrine are produced by the adenyl medulla where chroma fin cells produce these hormones. These hormones are amine hormones and they target most tissues of the body. Their primary actions include to increase the cardiac activity, induce vasoconstriction, increase glycolysis and lipolysis as a result they cause hyperglycemia. Their secretion is stimulated by sympathetic stimulation and controlled through simultaneous release of ATP. Dear students, another major metabolic hormone is the thyroxine produced by thyroid gland. It is an amine hormone and it targets most cells of the body especially muscles, blood, liver and kidney. Its primary actions include to increase the metabolic rate and thermogenesis. It promotes growth and development and also promotes metamorphosis in amphibians. The thyroid stimulating hormone from pituitary induces its release from thyroid gland while its secretion is controlled by negative feedback to pituitary and hypothalamus decreasing the TSH and TRH secretions that decrease the thyroxine secretion. Dear students, the major developmental hormone of the body is growth hormone which is secreted by the anterior pituitary adenyl hypophysis. It is a protein hormone and it targets almost all tissues of the body. Its primary action is that it stimulates RNA and protein synthesis and as a result promotes tissue growth. It also increases the uptake of glucose and amino acids by the cell. These are metabolic roles and it also increases the lipolysis. The growth hormone's production or release is enhanced when the plasma glucose level decreases in blood and at a time amino acid level increases. The release of growth hormone inhibits the somatostatin hormone. Dear students, we see that the processes of growth and development of animals are related to its rate of metabolism. These processes are controlled and integrated by the coordinated activity of these hormones.