Celine Cercado p.2 Endocrine System
Major functions of the Endocrine system
Major endocrine glands/organs and their functions (separate by region/ body cavity)
hormones produced, their functions and their target organs
Compare and contrast steroid vs. non-steroid hormones and list the hormones for each
category
Homeostatic mechanisms of hormone regulation (negative and positive feedback)
Diseases associated with the endocrine system
Steroid
lipid-soluble, they can pass through cell membranes
carried in blood stream... weakly bound to plasma proteins
are located inside the target cell
nonsteroid
combine with receptors in target cell membrane
hormones called 1st messenger
2nd messengers cause changes in the cell
thyroid
Hypothyroidism
causes low metabolic rate, fatigue, & weight gain the adults
infants: cause cretinism, poor growth & bone formation, abnormal mental development, and sluggish.
hyperthyroidism
causes high metabolic rate, restlessness, overeating in adults
over activity in the thyroid gland
Diabetes Mellitus
Metabolic disease due to lack of insulin or inability of cells to recognize insulin
Parathyroid Hormone
Hypoparathryoidism
Deficiency PTH due to surgical removal/ injury to glands
results in decrease in blood calcium
Hyperparathyroidism
Excess of PTH, due to parathyroid tumor
results in an increase in blood calcium
Type 1 diabetes mellitus
an autoimmune disorder
beta cells are destroyed, so insulin production decrease/ stops
Type 2 diabetes
When insulin is produced but isn't recognized by cells
Pituitary Gland
Release & Inhibits hormones from hypothalamus
Thyroid Gland
Parathyroid Gland
Adrenal Gland
Pancreas
Reproductive glands
Kidneys
Thymus Gland
Helps control calorie intake & helps regulate blood calcium levels & bone growth
Maintain homeostasis
hormones diffuse into the bloodstream to act on specific target cells
2 major types of glands
exocrine
endocrine
Increases blood calcium ion concentration & decrease phosphate ion concentration
enclosed in a layer of of adipose and connective tissue.
secretes hormones as an endocrine gland & digestive juice into digestive tract as an exocrine gland
Ovaries
Produce estrogen & progesterone
Testes
produce testosterone
Placenta
produces estrogen, progesterone, & gonadotropin
secretes erythropoeith for blood cell production
secretes thymosines affect production & differentiation of T lymphocytes
Negative
releases hormones from hypothalamus, controls of anterior pituitary hormones
Nervous system influences certain endocrine glands directly
other glands respond directly to change in internal fluid composition
controls hormone release
gland sensitive to concertraction of substance it regulates
Growth Hormones
Stimulates body cell to grow & reproduce
GHRH increases the amount of GH secreted, GH inhibiting hormone
Speeds the rate at which cells use carbohydrates & fats
prolactin
promotes milk production following the birth of an infant
controlled by releasing (PRF) & inhibiting hormone (PIH) from the hypothalamus
Target: bones, muscle & joints
Target: mammary gland
Thyroid-stimulating
control secretion of hormones of thyroid gland
TRH from hypothalamus stimulates the release of TSH
Blood concentration of thyroid hormones increase
Target: thyroid gland
Adrenocorticotropic
regulated by CRH from hypothalamus
stress can increase release CRH, decreases ACTH secretion
Target: Adrenal Cortex
Follicle- stimulating
females develop egg-contain
males: production of sperm cells
Target: ovaries and testes
Luterinizing
sex hormones: released egg cells in female
Target: Ovaries and testes
Antidiuertic
kidneys to conserve water, reduce amount of water in urine
high level causes vasoconstriction of blood vessels, helps maintain blood pressure
Oxytocin
plays a role in childbirth, by contracting muscle in urine wall, milk-let down
stretching of uterus in latter stages of pregnancy release OT
suckling of infants at breast release OT after birth
Target:: Uterine smooth muscle & mammary gland
Thyroid Gland
Thyroxine (T4)
Increases energy release carbohydrates
protein synthesis accelerating growth
Target: Most tissues
Triiodothyronine (T3)
5 times more potent than thyroxine
Calcitonin
lowers blood concentration by stimulating deposition of calcium & phosphate ions into bones
same as Throxine
Target: Bone
Parathyroid Glands
Parathyroid hormone
increases blood calcium ion concentration & decreases phosphate ion concentration
stimulates bone resorption by osteoclasts, releases calcium into the blood
stimulates kidneys to conserve calcium
Targets: Bone, Kidneys, & intestines
Adrenal Cortex
Aldosterone
helps regulate mineral or electrolyte balance
causes kidneys to conserve sodium ions & thus water & to excrete potassium ions
Cortisol
produced cells of middle layer
promotes fatty acids release adipose tissue, increasing use fatty acids for energy & decrease use glucose
Pancreas
Glucagon
increases blood lever of glucose by stimulating the breakdown of glycogen & conversion of noncarbohydrates into glucose
release glucagon is controlled by negative feedback
low blood glucose level stimulates the secretion of glucagon
Insulin
decrease blood level of glucose by stimulating liver form glycogen
release of insulin's controlled by negative feedback
high blood glucose stimulates release of insulin
coordinates to maintain a relatively stable blood glucose concentration