Functions of Hormones in Human Body

Hormone Produced by Function
GastrinStomachIt stimulates the stomach to release gastric acid and also stimulates growth of the stomach lining.
GlucagonIslet of Langerhans (Pancreas)It prevents blood glucose levels dropping too low.
InsulinPancreasIt controls how the body uses carbohydrate and fat found in food. It causes cells in the liver, skeletal muscles and fat tissue to absorb glucose from the blood.
CholecystokininDuodenumIt slows down the emptying of food from the stomach and also stimulates the production of bile thus improving digestion.
MelatoninPineal GlandIt is often called a sleep hormone. We sleep better when melatonin is secreted.
Oestradiol (Estradiol) (E2)OvariesStrongest of the three Estrogens viz. Oestrone, Oestradiol and Oestriol. The main function is to mature and maintain the female reproductive system.
Oestriol (E3)PlacentaThe levels increase during pregnancy and are highest just before birth. Since the chemical from which it is made comes exclusively from the adrenal glands of the baby, the levels are an indicator of the health of the foetus.
Oestrone (E1)Ovaries, Adipose tissue and Adrenal GlandsMajor type of Oestrogen in post-menopausal women.
OxytocinHypothalamusIt causes the contraction of the womb (uterus) during childbirth and lactation. It also promotes the movement of milk into the breast, allowing it to be excreted by the nipple. In men it plays a role in sperm movement and production of testosterone by the testes. It has been called the love hormone due to its role in human behaviour like sexual arousal, mother-infant bonding etc.
ProgesteroneCorpus Luteum in the OvaryCorpus Luteum is a structure formed by remnants of ovarian follicle which enclose the egg during its formation. Progesterone released by this prepares the body for pregnancy in the event that the released egg is fertilised. If the egg is not fertilised, the corpus luteum breaks down, the production of progesterone falls and a new menstrual cycle begins..
TestosteroneTestes in Men, Ovaries in WomenIn men, it initiates the development of the male internal and external reproductive organs during foetal development and is essential for the production of sperm in adult life. It is also responsible for many of the changes seen in boys during puberty. In women, testosterone produced in the ovary is converted to the principle female sex hormone, oestradiol.