Chapter 15 Flashcards
endocrine glands release
hormones that influence other parts of the body
hormones enter from where
enter blood & travel to target cells with receptors
hormones are critical for maintaining
homeostasis
peptide hormones
start chain of reactions
peptide hormones - more specific
usually don’t enter cell, use second messengers
activating enzymes in peptide hormones
starts cascade of reactions, ex: epinephrine, cAMP, breakdown of glycogen
steroid and other lipid hormones bind
inside cells
steroid and other lipid hormones enter
cells directly and find receptors there (often in nucleus)
steroid and other lipid hormones have a ______ effect
slower effect, making new proteins, longer lasting effect
when regulates the secretion of hormones
feedback mechanisms
negative feedback vs positive feedback
negative feedback is important for stability and homeostasis
positive feedback is less common
where is the pituitary gland located
base of brain
two lobes of the pituitary gland
anterior: larger; circulatory connection to hypothalamus, ex: growth hormone
posterior: very small; neural connection to hypothalamus, stores hormones made in hypothalamus, ex: oxytocin:child birth and lactation
growth hormone
stimulates growth - cell size & division
direct effect on cells
indirect by stimulating other hormone release
too much growth hormone
giantism; acromegaly
too little growth hormone
pituitary dwarfism
thyroid gland location
front of neck
hormones in the thyroid gland
thyroid hormones: T3&T4 - # of iodine atoms, stimulate all cells to metabolize at faster rate
calcitonin: decreases blood calcium levels
parathyroid glands: location & hormones
4 small glands @ back of thyroid, parathyroid hormone: increases blood calcium levels
thyroid hormones
- congential hypothyroidism: affects growth and results in mental retardation
- goiter-enlargement of thyroid when not enough iodine
adult hypothyroidism results in
fluid build up in face, decreased alertness, body temp and heart rate
hyperthyroidism
increases metabolism, heart rate, sweating, nervousness, weight loss, protruding eyes from edema
where are the adrenal glands located and what are the two parts?
located on top if kidneys
parts: cortex (outer) and medulla (inner)
medulla secretes
epinephrine & norepinephrine
epinephrine & norepinephrine function
short term stress hormones, raise heart rate, blood pressure & blood glucose, dilate skeletal and cardiac blood vessels, constrict digestive vessel
the cortex secretes
greater than 20 hormones including glucocorticoids & mineralocorticoids, help with a long term response to stress
glucocorticoids
secreted by the cortex in adrenal glands, regulates carbohydrate, fat & protein metabolism, decrease inflammation response
mineralocorticoids
ion balances, secreted by the cortex in adrenal glands
where is the pancreas located
behind the stomach , exocrine & endocrine role
role of the pancreas
glucose regulation
glucagon
in the pancreas increases glucose in the blood, make in liver from glycogen, lactic acids, and amino acids
insulin
decreases glucose in blood, inhibits glycogen breakdown; promotes glucose transport into muscle & white blood cells; prevents glucose from forming, results in promoting protein synthesis, fat storage & energy from glucose use
diabetes mellitus
high levels of glucose in the blood
type 1 diabetes
autoimmune disorder-no insulin is made, need insulin plus careful blood monitoring
type 2 diabetes
decreases sensitivity to insulin, often managed with weight loss, diet and exercise
serious long term risks of diabetes
blindness, kidney disease, heart disease, high blood pressure, artherosclerosis, gum disease, nervous system damage, poor circulation
other endocrine glands & functions etc.
testes and ovaries: sex hormones that give secondary sex characters, sperm formation in males & menstrual cycle in females
pineal gland: melatonin and sleep-wake cycle
