Card Set Information
Holes Human Anatomy and Physiology
What are the general characteristics of the
releases hormones into the bloodstream
regulate metabolic processes
What is a hormone?
substance secreted by an endocrine gland and transported in the blood
What is the basic function of a hormone?
stimulate changes in target cells even in extremely low concentrations
What are paracrine substances?
synthesized from a type of fatty acid in cell membranse
produce liver, kidney, heart, lungs, thymus gland, pancreas, brain and reproductive organ cells
What are autocrine substances?
affect only secreting cells
Define steroid hormones
derived from cholesterol
include sex hormone
secretions from adrenal cortex
Define nonsteroid hormones?
derived from amino acid tyrosine
synthesized in the adrenal medulla
How do steroid and nonsteroid hormones affect their target cells?
steroid:combine with specific protein receptors
: combines with specific receptor molecules
What are prostaglandins?
paracrine substances, are potent and present in small amounts
How do prostaglandins function?
they are not stored, they are synthesized just before they are released
regulate cellular responses to hormones
How does the nervous system aid in the regulations of hormones?
directly stimulates some glands
How does the hypothalamus aid in the regulation of hormones?
controls the anterior pituitary gland's releade of tropic hormones, which stimulate other endocrine to glands release hormones
How does the internal environment aid in the regulation of hormones?
group of glands responds directly to changes in environment
(blood glucose rises, pancreas secretes insulin)
Describe the negative feedback system
mechanism that restores a biochemical or other balance in which build up of a product suppresses its synthesis
at the base of the brain
attached to the hypothalamus
lies in the stella turcica
vascular structure that consists of two large lateral loves connected by a broad isthmus
below the larynx on either side and anterior to the trachea
on the posterior suface of the thyroid gland
usually 4 of them
a gland sits atop each kidney like a cap and is embedded in the mass of adipose tissue that encloses the kidney
elongated, somewhat flattened organ posterior to the stomach and behind the parietal peritoneum
small oval structure deep between the cerebral hemispheres, attached to the upper portion of the thalamus
thyroid stimulating hormone
secretes the protein parathyroid hormone
epinephrine aka adrenalin
norepinephrine aka noradrenalin
lies in the mediastinum posterior to the sternum and between the lungs
stimulates increase in size and rate of division of body cells; enhances movement of amino acids
Growth Hormone (GH)
sustains milk production after birth; amplifies effect of LH in males
controls secretion of hormones from the thyroid gland
thyroid stimulating hormone (TSH)
controls secretion of certain hormones from the adrenal cortex
development of egg-containing follicles in ovaries; stimulates follicular cells to secrete estrogen;in males, stimulates production of sperm cells
follicle-stimulating hormone (FSH)
promotes secretion of sex hormones; release egg cells in females
causes kidneys to reduce water excertion; in high concentration, raises blood pressure
contracts muscles in uterine wall and those associated with milk secreting glands
increases rate of energy release from carbohydrates; increases rate of protein synthesis; accelerates growth; stimulates activity in nervous system
increases rate of energy release from carbohydrates; increases rate of
protein synthesis; accelerates growth; stimulates activity in nervous system.....5 times more potent
lowers blood calcium and phosphate ion concentrations by inhibiting release of calcium and phosphat ions from bones
helps regulate the concentration of extracellular electrocytes by conserving sodium ions and excreting potassium ions
decreases protein synthesis, increases fatty acid release and stimulates glucose synthesis from noncarbohydrates
supplement sex hormones from the gonads; may be converted into estrogens
stimulates the liver to break don glycogen and convert noncarbohydrates into glucose; stimulates breakdown of fats
promotes formation of glycogen from glucose, inhibits conversion of noncarbohydrates into glucose and enhances movement of glucose through adipose and muscle cell membranse
helps regulate carbohydrates
insufficient secretion of human growth hormone during childhood produces
high metabloic rate, sensitivity to heat; restlessness, hyperactivity, weight loss, protruding eyes, goiter
autoantibodies bind TSH receptors on thyroid cell membrans, mimicking action of TSH, overstimulating gland and goiter
autoantibodies attack thyroid cells, resulting in hypothyroidism
cretinism-stunted growth, abnormal bone formation, mental retardation, low body temperature, sluggishness
myxedema-low metabolic rate; sensitivity to cold, sliggishness, poor appetite, swollen tissues, mental dullness
deficiency of thyroid hormones due to iodine deficiency; because no thyroid hormones inhibit pituitary release of TSH, thyroid is ocerstimulated and enlarges but functions below normal
fatigue, muscle weakness, painful joints, altered mental functions, depression, weight loss, bone weakening, increased PTH secretions overstimulaates osteoclasts
muscle cramps and seizures, decreased PTH secretion reduces osteoclast activity, diminishing blood calcium ion concentration
decreased blood sodium, increased blood potassium, low blood glucose level, dehydration, low blood pressure, frequesnt infections, fatigue nasuea and vomitting, increased skin pigmentation
the pancreas can not produce insulin
symptoms begin before age twenty
juvenile of insulin dependent)
Type 1 diabetes mellitus
ususally in people over 40
cells lost insulin receptors and are less able to respond to insulin
Type II diabetes mellitus
impars ADH regulation of water balance
Which part of the brain controls your response
threatens tissues, extreme heat or cold, decreased oxygen concentration, infections, injuries, prolonmges heavy exercise
results from thoughts about real or imagined dangers, personal losses, unpleasent social interactions
Which hormones are involved in the stress response?
corticotropin releasing hormone
Which systems are affected by stress?
autonomic nervous system
List some the life span changes seen in the endocrine system.
endocrine glands shrink and accumulate fibrous connective tissue, fat and lipofuscin
hormone the adrenal medulla secretes during times of stress
neurotransmitter released from the axons of some nerve fibers