HormonesHormonesTopic B6Topic B6

Production and function Production and function (B.6.1)(B.6.1)

primarily chemical messengers

produced in endocrine glands– organs that secrete directly

into bloodstream and transported to various target cells in the body

hormone examples hormone examples are…….are…….

epinephrine (adrenaline)epinephrine (adrenaline)– produced in the adrenal glandsproduced in the adrenal glands

– the ‘fight or flight’ hormonethe ‘fight or flight’ hormone

– stimulantstimulantdilates pupils and airways, increases blood dilates pupils and airways, increases blood supply to heart and musclessupply to heart and muscles

thyroxinethyroxine– produced in the thyroid glandproduced in the thyroid gland– regulates the body’s regulates the body’s

metabolismmetabolism

ADH (antidiuretic hormone)ADH (antidiuretic hormone)– produced in the hypothalamusproduced in the hypothalamus– most important function is to conserve water most important function is to conserve water

by reducing the amount of water passed out by reducing the amount of water passed out in the urinein the urine

aldersteronealdersterone– produced in the adrenal glandsproduced in the adrenal glands– serves as the principal regulator of the salt and

water balance of the body

estrogen– produced in the ovaries– primary female sex hormones– promote the development of female secondary

sexual characteristics– involved in the thickening of the endometrium and

other aspects of regulating the menstrual cycle

progesteroneprogesterone– produced in the ovaries and the adrenal

glands– plays important roles in the menstrual cycle

and in maintaining the early stages of pregnancy

testosterone– secreted primarily by the testes– promoting secondary sexual characteristics

such as increased muscle, bone mass, and the growth of body hair

insulininsulin– protein (51 amino acids) produced in the

pancreas– regulates blood sugar by

triggering cells to uptake sugar

stimulating the liver to store glucose in the form of glycogen

– diabetics produce too little insulin

CompareCompare structures of cholesterol and structures of cholesterol and sex hormones sex hormones (B.6.2)(B.6.2)

all are steroidsall are steroids

all have backbone consisting of three six-all have backbone consisting of three six-membered rings and one five-membered ring membered rings and one five-membered ring fused togetherfused together

but they differ in the type and position of but they differ in the type and position of functional groups functional groups on the steroid backboneon the steroid backbone

cholesterol

MaleMale FemaleFemale

Oral contraceptives Oral contraceptives (B.6.3)(B.6.3)

most commonly used is called the most commonly used is called the combined oral contraceptive pill combined oral contraceptive pill

– contains a combination of estrogen and contains a combination of estrogen and progesteroneprogesterone

take these for 21 daystake these for 21 days

then a placebo for 7 days so period still then a placebo for 7 days so period still occurs but no release of eggsoccurs but no release of eggs

– mimics pregnancy by keeping hormones mimics pregnancy by keeping hormones at high levelsat high levels

prevents ovulation from occurringprevents ovulation from occurring

makes the lining of the uterus thinner so makes the lining of the uterus thinner so that it is unsuitable for implantation of a that it is unsuitable for implantation of a fertilized eggfertilized egg

makes the mucus in the cervix thicker to makes the mucus in the cervix thicker to prevent sperm from reaching the eggprevent sperm from reaching the egg

Use and abuse of steroids (anabolic) (B.6.4)

useuse–the “pill” as previously mentionedthe “pill” as previously mentioned–hormone replacement therapy (HRT) for women hormone replacement therapy (HRT) for women going through menopausegoing through menopause–promote increased muscle mass and growth after promote increased muscle mass and growth after a serious illness or injurya serious illness or injury

abuseabuse–can enhance athletic performance in order to win can enhance athletic performance in order to win competitionscompetitions

– taking large doses cause harmful side effects – in men: impotence, baldness, problems in

urinating, smaller testes– in women: changes in secondary sex

characteristics, build up of muscles and increased facial hair

– both men and women also experience • violent temper/aggressive behavior• liver tumors, high blood pressure and heart attacks