THE ENDOCRINE SYSTEM

GENERAL FUNCTIONS:

1. Endocrine glands secrete chemicals (_______________) into the blood.

2. Hormones perform general functions of _______________ and _______________, a _______________, longer-lasting type of control than nerve impulses

3. Cells acted on by hormones are called _______________ organ cells

_______________ - too much secretion

_______________ - too little secretion

ANTERIOR PITUITARY GLAND - Also called _______________

Often called "_______________"

Functions:

1. ______________________________ (TSH) - Stimulates growth of thyroid gland and the production of thyroid hormone

2. ______________________________ (ACTH) - Stimulates growth of adrenal cortex and production of _______________, especially hydrocortisone

3. ______________________________ (FSH) - Initiates growth of ovarian follicles each month in ovary; stimulates one or more follicles to mature and ovulate; stimulates _______________ secretion; stimulates _______________ production in males

4. ______________________________ (LH) - Stimulates estrogen; causes _______________; causes ruptured follicle to become the corpus luteum and stimulate _______________ production.

5. ______________________________ (ICSH) - same as LH, but in male causes interstitial cells in testes to secrete _______________

6. Melanocyte Stimulating Hormone (MSH)

Causes rapid increase in synthesis and spread of melanin (pigment) in the skin

7. ______________________________ (GH) - Stimulates growth by accelerating protein anabolism; accelerates fat catabolism; slows glucose catabolism and raises glucose levels

8. ______________________________ (PRL) - Stimulates breast development during pregnancy and milk production after delivery

GROWTH HORMONE ABNORMALITIES

_______________ - due to hypersecretion of GH in early years

_______________ - due to hyposecretion of GH in early years

_______________ - due to hypersecretion of GH in adult years

POSTERIOR PITUITARY GLAND - Also called _______________

Hormones:

1. ______________________________ (ADH) - Accelerates water _______________ from urine in kidney tubules into blood, thereby _______________ urine secretion - Alcohol inhibits ADH.

______________________________ - caused by hyposecretion of ADH; patients may excrete 25 to 30 liters of urine in 24 hrs. causing extreme thirst and dehydration

2. _______________ (OT) - Stimulates pregnant uterus to _______________; may initiate labor; causes glandular cells of breast to _______________ milk into ducts (let-down).

Pressure on cervix stimulates brain to release _______________. Contraction causes more _______________ and more oxytocin. (_______________ feedback mechanism) Cycle is broken when _______________ decreases pressure on cervix.

_______________ (synthetic oxytocin) may be given to initiate labor.

HYPOTHALAMUS

Actual _______________ of ADH and oxytocin occurs in _______________.

Supraoptic neurons secrete ADH.

Paraventricular neurons secrete oxytocin.

Hormones pass into _______________ gland after production where they are stored and released. Controls many body functions such as _______________, _______________, and _______________.

THYROID GLAND

1. Thyroid hormones

______________ (T₄) & Triiodothyronine (T₃) - Accelerates _______________ of all cells

_______________ - due to excess secretion of thyroid hormones; _______________ metabolic rate causing loss of weight, nervousness, irritability, protruding eyes (I call it Barney Fife Syndrome)

_______________ - due to undersecretion of hormones; may cause:

a. _______________ - due to undersecretion during formative years; characterized by low metabolic rate, retarded growth and sexual development, frequent mental retardation

b. _______________ - due to undersecretion during the adult years; characterized by lessened mental and physical vigor, weight gain, loss of hair, accumulation of fluid

c. _______________ - due to low dietary intake of iodine; characterized by increased size of thyroid gland.

2. _______________ (CT) - _______________ blood calcium levels by inhibiting release of bone calcium into blood by inhibiting _______________

PARATHYROID GLANDS

Hormone = _______________ (PTH)

Function -_______________ blood calcium by increasing the breakdown of bone by _______________, also increases resorption of calcium by kidneys.

Works in opposition to _______________ to balance calcium levels in blood.

_______________ can cause neurons to depolarize spontaneously causing muscle twitches, spasms, convulsions, and cramps. This condition is called _______________.

_______________ causes decalcification of the bones.

ADRENAL GLANDS

The adrenal glands are divided into the _______________ (outer layer) and the _______________. The cortex and medulla have different functions.

Cortex Structure: 3 layers

Zona _______________ - outer layer

Zona _______________ - middle layer

Zona _______________ - inner layer

Adrenal Cortex Hormones:

1. _______________ - (aldosterone) - Secreted in the Zona _______________

Mineralocorticoids _______________ blood sodium, decrease potassium levels.

2. _______________: cortisol (hydrocortisone)

Secreted in the Zona _______________

Functions of glucocorticoids:

a. maintains _______________ levels by increasing _______________ (converting fats and proteins to glucose)

b. Assists in maintaining proper _______________ for normal blood pressure.

c. Acts with epinephrine and norepinephrine to produce anti-_______________ effect

d. Produces anti-immunity, _______________ effects, decreases lymphocytes (therefore decreasing antibodies)

e. Stimulated by stress and initiates stress reponses

3. Sex Hormones - Androgens & Estrogens produced in both sexes

Secreted in the Zona _______________

_______________ - male hormones

_______________ - female hormones

_______________ of androgens in the female may cause masculine traits such as beards, baldness, and/or muscular physique.

Hypersecretion of estrogens in the male may cause _______________ = excessive growth of the male mammary glands.

Adrenal Medulla Hormones:

1. Epinephrine = _______________

2. Norepinephrine = _______________

Function of Epinephrine and Norepinephrine:

Stimulate the "______________________________" responses:

acceleration of heartbeat, constricts most blood vessels but dilates blood vessels to skeletal muscles, decreases peristalsis of digestive tract, inhibits defecation and urination, dilates pupils, stimulates goose pimples, increases sweat, decreases digestive juices, increases respiration, raises blood sugar.

ISLANDS (ISLETS) OF _______________ - Located in _______________

Hormones:

1. _______________ - secreted by alpha cells

Increases blood glucose by accelerating _______________ (breakdown of glycogen)

2. _______________ - decreases glucose in blood by accelerating movement of glucose into cells therefore increasing glucose metabolism. Also increases _______________ (conversion of glucose into glycogen).

Hyposecretion of insulin leads to a disorder known as ______________________________ in which there is too much sugar in the blood, leading to the excretion of sugar in the urine, a condition known as _______________.

Types of Diabetes:

Type I Diabetes - also called Juvenile Diabetes or _______________-dependent Diabetes is caused by a _______________ of insulin due to a _______________ in beta cells. The increased blood sugar may cause cataracts, ketosis (blood acidosis), atherosclerosis, vascular diseases, and kidney damage.

Type II Diabetes - also called _______________-onset Diabetes or Non-insulin-dependent Diabetes. This is most common, 90%, usually occuring around 40 yrs old. Symptoms are mild, usually controlled by diet alone.

FEMALE SEX CELLS - OVARIES

Ovarian Follicles produce ESTROGEN

Corpus luteum produces PROGESTERONE

We will study the functions of estrogen and progesterone later in the reproductive system.

MALE SEX GLANDS - _______________

Hormone - _______________ - Secreted by interstitial cells.

Promotes development of male sex organs and _______________ characteristics (voice change, body hair, facial hair, etc.)

THYMUS

Hormone = _______________

Plays important role in development of the T-lymphocyte cells in the immune system.

PLACENTA

Hormone = _______________ _______________

Function: Maintain the corpus luteum

_______________ GLAND - Cone-shaped gland under brain

Hormone = _______________

Inhibits gonadotropic activity; Influences menstrual cycle

Melatonin is produced during _______________. Light inhibits melatonin production so melatonin may be the body's way of keeping track of days.

Another hormone secretion, adrenoglomerulotropin, stimulates the adrenal cortex to produce aldosterone