Adrenaline• Is produced in the adrenal glands, which are located above the kidneys• It is a hormone produced by the endocrine system.• It excites us when we are in exciting or stressful situations by dilating our pupils and airways and increasing our heartbeats and the rate of release of sugar into our bloodstream.
Thyroxine• Produced in the thyroid gland located in the neck• Contains iodine• Regulates the body’s metabolism• Low levels of thyroxine cause hypothyroidism.• High levels of thyroxine lead to hyperthyroidism.
Insulin• Protein containing fifty-one amino acid residues.• Formed in the pancreas by the Islet of Langerhorn.• Regulates cellular intake of glucose from the blood. It is secreted when blood sugar or amino acid concentration rises.• Insulin also inhibits the breakdown of glycogen in the liver.• Low levels of insulin lead to hyperglycaemia.• High levels cause hypoglycaemia.
Aldosterone• Is produced in the adrenal cortex, which is part of the adrenal gland.• It manages sodium and potassium balance and maintains body fluid levels.
The Antidiuretic Hormone (ADH)• It is produced in the hypothalamus, but is released by the pituitary gland.• It is also called vasopressin.• It prevents the production of dilute urine and contracts the arteries and capillaries.
Sex Hormones• They are steroids that contain a four ring structure.• All steroids are produced from cholesterol, which is formed in the liver.• Male sex hormones- testosterone and androsterone, which are anabolic and androgenic, they are produced in the testes • Anabolic- encourages tissue, muscle, and bone growth • Androgenic- conferring with the male sexual characteristics• Female sex hormones- progesterone and oestradiol, they are produced in the ovaries, and are used in sexual development and in the menstrual and reproductive cycles
Male Hormones Female HormonesTestosterone ProgesteroneAndrosterone Oestradiol
B.6.2 Compare the structures of• Cholesterol and sex hormones have the same basic steroid base, but have different functional groups attached to the base. Cholesterol
B.6.3 Describe the mode of action of oral• During pregnancy when the egg is fertilized it is embedded in the uterine wall and the hormone levels rise. FSH ( follicle stimulating hormone) and LH (luteinizing hormone) facilitate the release of oestradiol and progesterone.• If the levels of oestradiol and progesterone are high than the body thinks it is pregnant so it won’t release the new egg, preventing pregnancy.
B.6.4 Outline the use and abuse of• Anabolic steroids are similarly structure to testosterone.• Some approved uses are for recovery from illnesses and muscle strengthening.• Some abuses of steroids are athletes trying to approve their athletic abilities. Anabolic Steroids