Hormones. Follicle Stimulating Hormone

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1 Endocrine System

2 Hormones Hormones are chemical substances created by the body that control numerous body functions. They actually act as "messengers" to coordinate functions of various body parts. Follicle Stimulating Hormone

3 Tropic Hormones Tropic hormones regulate the activities of other endocrine hormones

4 Endocrine glands These secrete their products into the blood

5 Posterior Pituitary This stores two hormones made in the Hypothalamus

6 Oxytocin Oxytocin stimulates the uterine contractions of labor that are needed to move the child out through the birth canal. The hormone stimulates the release of milk from the mammary glands by causing surrounding cells to contract. After birth, stimulation of the breast by the infant feeding stimulates the posterior pituitary to produce oxytocin.

7 Antidiuretic Hormone (ADH) Antidiuretic hormone increases the permeability of the distal convoluted tubule and collecting duct of the kidney nephron resulting in less water in the urine. The secretion of ADH is controlled by a negative feedback mechanism as follows: concentrated blood hypothalamus ADH kidney reabsorbs water, makes blood more dilute

8 Negative Feedback

9 Positive Feedback

10 Anterior Pituitary

11 Growth Hormone (GH) Also known as Human Growth Hormone (HGH) Growth hormone stimulates body cells to grow. Too little hormone causes, pituitary dwarfism, too much hormone results in a pituitary giant. Acromegaly is a genetic disease in which growth hormone is produced throughout a persons lifetime. Robert Wadlow 8 11

12 Melanocyte-Stimulating Hormone (MSH) This hormone causes skin color changes in some fishes, amphibians, and reptiles. In humans, it stimulates the melanocytes to synthesize melanin.

13 Luteinising hormone (LH) & Follicle Stimulating Hormone (FSH) In males, LH has been known as Interstitial cell stimulating hormone LH stimulates the testes to produce steroid hormones (androgens) including testosterone. LH stimulates the ovaries produce estrogen and progesterone, the female sex hormones. FSH controls gamete (egg or sperm) production.

14 Adrenocorticotropic hormone (ACTH) Also called corticotropin Stimulates the adrenal cortex to produce hormones (gluco- and mineralocorticosteroids, and androgenic steroids}

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17 Pineal Gland The mammalian pineal gland evolved from a photoreceptive organ in lower vertebrates, a functional third eye. The Pineal gland produces melatonin which helps to regulate the sleep/wake cycle. The raw material used to made melatonin is the amino acid tryptophan which is first converted into serotonin, then into melatonin. Have profound effects on homeostasis, immune surveillance and the maintenance of connective tissue.

18 Thyroid Gland

19 Produces T4 (thyroxine) and T3 (triiodothyronine) T4 is produced in greater quantities, but when is arrives at the target tissue it is converted to T3, which is the more active form. Thyroid hormone controls the body s metabolism and growth. Undersecretion in childhood leads to cretinism and dwarfism, in adults it is known as Hypothyroidism (myxoedema). The opposite state, Hyperthyroidism (thyrotoxicosis), is most commonly caused by Graves Disease, an auto-immune condition Also produces CALCITONIN which reduces blood calcium levels

20 Parathyroid Glands Four small patches of tissue on the back of the thyroid make up the parathyroid glands. They produce Parathyroid hormone (aka parathormone) which breaks down bone to release calcium.

21 Pancreas The pancreas secretes Insulin which stimulates excess blood glucose to be stored as glycogen in the liver and muscles A second hormone, Glucagon, balances Insulin by raising levels of blood glucose Type 1 diabetes occurs when the body is unable to produce any insulin. This type of diabetes usually appears before the age of 40.Type 2 diabetes is the most common kind. This is when the body can still make some insulin, but not enough, or when the insulin that is produced has very little effect (insulin resistance).

22 Thymus Gland The thymus develops and matures T-lymphocytes. These help other immune cells recognize and destroy invading bacteria, virus, etc., abnormal cell growth such as cancer, and foreign tissue. It produces thymosin, a hormone which promotes the development of immunesystem cells.

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