a&p2 final ch18

exocrine glands

secrete products into duct

endocrine glands

secretes products into bloodstream

heterocrine glands

both endocrine and exocrine functions

target cells

cells that have specific receptors for a hormone and respond to that hormone’s signal

difference between positive and negative feedback

negative feedback reduces/shuts off original stimulus (insulin regulation) (maintains homeostasis); positive feedback amplifies original stimulus (childbirth)

describe the two lobes of the pituitary gland

anterior lobe (adenohypophysis) and posterior lobe (neurohypophysis)

adenohypophysis

makes and releases hormones like hGH, ACTH, TSH

neurohypophysis

stores and releases hormones made by the hypothalamus (oxytocin and ADH)

number of hormones released by hypothalamus

9 (7 for adeno and 2 for neuro)

hormones released by anterior pituitary (adenohypophysis)

GH (growth hormone), ACTH, TSH, FSH, LH, PRL (prolactin), MSH

growth hormone function

stimulates growth and cell reproduction

ACTH function

stimulates adrenal cortex to release cortisol

TSH

releases thyroid hormone

FSH

stimulates egg/sperm production

LH

triggers ovulation/testosterone production

prolactin

stimulates milk production

MSH

affects skin pigmentation

hormones released by posterior pituitary (neurohypophysis)

oxytocin, ADH

oxytocin

stimulates uterine contraction and milk ejection

ADH (antidiuretic hormone)

reduces water loss by increasing water reabsorption in kidneys

hormones released by thyroid

T3, T4, calcitonin

T3 and T4

regulate metabolism, heartrate, and temp

calcitonin

lowers blood calcium levels by promoting calcium storage in bones

hormone released by parathyroid

PTH

parathyroid hormone (PTH)

raises blood calcium levels by stimulating bone breakdown and increasing calcium absorption in kidneys and intestines

hormones released by adrenal cortex

aldosterone, cortisol, androgens

aldosterone

regulates sodium and potassium levels

cortisol

helps control metabolism and stress response

androgens

supports development of sex characteristics

hormones released by adrenal medulla

epinephrine and norepinephrine

epinephrine/norepinephrine

triggers fight or flight response; increase heart rate, BP, and energy availability

where are endocrine cells found in the pancreas

islets of langerhans

alpha cells

release glucagon; raises blood sugar

beta cells

release insulin; lowers blood sugar

sex hormones

estrogen, progesterone, testosterone

hormones produced by ovaries

estrogen and progesterone

hormone produced by testes

testosterone

secondary sex characteristics

physical traits that appear during puberty that distinguish males from females

hormone released by pineal gland

melatonin

melatonin

regulates sleep-wale cycles
(circadian rhythms)

where is the thymus located

in the upper chest behind the sternum

how does the thymus shrink as we age

it shrinks and becomes mostly fatty tissue after puberty

what do thymic hormones do

help develop and mature T cells

hormones released by the kidneys

erythropoietin (EPO), renin, calcitriol

erythropoietin

stimulates RBC production

renin

regulates BP

calcitriol

active form of vitamin D; increase calcium absorption

hormone released by heart

atrial natriuretic peptide

atrial natriuretic peptide
(ANP)

lowers BP by causing kidneys to excrete sodium and water

grave’s disease

causes hyperthyroidism (leads to weight loss, fast heartbeat, bulging eyes)

disorders caused by irregular release of HGH

too much in kids (giantism), too much in adults (acromegaly), too little (dwarfism)