Biology 172 FINAL EXAM: Hormones and the Endocrine System

1) secrete chemicals into ducts that empty onto a surface or into a cavity or space
2) examples
a) sweat gland
b) salivary gland

a. secrete chemicals (hormones) directly into intercellular spaces (not through ducts)
b. hormones then diffuse into the blood stream (not through ducts)
c. hormones circulated through blood eventually encountering target organs

target cells found near the secreting cell

target cell is the same cell as the secreting cell

involves neurotransmitters that diffuse across syapses to post-syaptic neuron target cells

neurosecretory cell secretes neurohormones into the blood which transport these chemicals to their respective target cells

Primary Functions of Hormones (5)

examples
a. insulin
b. glucagon
c. growth hormone
d. oxytocin
e. calcitonin
f. antidiuretic hormone (ADH)

1. derivatives of cholesterol
2. examples
a. testosterone
b. estradiol
c. cortisol

1. derivatives of the amino acid tyrosine
2. examples
a. tyrosine
b. thyroxine
c. epinephrine

a. stimulate the production of hormones from other endocrine glands
b. example: thyroid-stimulating hormone produced by the pituitary stimulates the thyroid to release thyroxine)

a. stimulate cells to behave in a certain way
b. example: thyroxine stimulates increased metabolic rate and growth of cells

Water-Soluble Hormones

Lipid-Soluble Hormones

1. found beneath the brain connected to the hypothalamus
2. functions as a "master" gland by secreting hormones that affect the functioning of other endocrine glands (produces tropic hormones)
3. really two glands in one: the anterior and posterior

1) terminal ends of hypothalamic neurons release hormones from this section of the pituitary
2) thus, these hormones are ultimately the product of the hypothalamus
3) hormones
a) antidiuretic hormone (ADH; acts on kidney tubules)
b) oxytocin (acts on mammary glands and uterine muscles)

1) stimulated to secrete hormones by chemicals (releasing factors) released by neurosecretory cells in the hypothalamus
2) releasing factors transported into the anterior pituitary via a portal system
3) hormones of the anterior pituitary
a) growth hormone (GH)
b) thyroid-stimulating hormone (TSH)
c) adrenocorticotropic hormone (ACTH)
d) gonadotropins 
e) melanin-stimulating hormone (MSH)
f) prolactin

1) acts on the liver, stimulating it to release several polypeptide hormones (insulin-like growth factors, IGFs)
2) stimulates amino acid uptake and protein synthesis in target cells
3) ultimately stimulates cell growth (cell size and number), especially in muscle and bone
4) stimulates fat breakdown
6) abnormalities
a) undersecretion during growing years =dwarfism
b) oversecretion during growing years = gigantism
c) excess GH after growth is complete = acromegaly

1) stimulates the release of thyroxine and triiothyronine by the thyroid
2) thyroxine and triiodothyronine increase glucose catabolism and body heat production

1) stimulates the release of glucocorticoids (e.g., cortisol) from the adrenal cortex
2) glucocorticoids increase levels of glucose, amino acids, and fatty acids in the blood

1) follicle stimulating hormone (FSH)
2) interstitial cell stimulating hormone (ICSH)
3) luteinizing hormone (LH)

1. found in the brain
2. associated with body responses to light
3. secretes melatonin which is associated with biological rhythms

1. found in the neck just below the larynx
2. its hormones require iodine
3. hormones stored in thyroid follicles

1) increase glucose metabolism and body heat production (thus increases metabolic rate of the body)
2) negative feedback mechanism involved in regulating levels

calcitonin ______ calcium levels in the blood by stimulating calcium deposition in bone

swelling of the thyroid due to lack of iodine

1) = reduced thyroid activity
2) leads to reduced metabolic activity and alertness

1) = accelerated thyroid activity
2) leads elevated metabolic activity
3) may lead to Graves' disease

1. four small glands located on the posterior side of the thyroid
2. secretes parathyroid hormone (PTH) which acts in opposition to calcitonin

a. increases blood calcium levels by stimulating the release of calcium from bone
b. reduces excretion of calcium by kidneys
c. converts inactive vitamin D to its active form

1. endocrine function associated with the islets of Langerhans
2. pancreatic hormones
a. glucagon
b. insulin

1) secreted by alpha cells
2) functions
a) stimulates glycogenolysis (breakdown of glycogen) in the liver
b) stimulates gluconeogenesis (synthesis of glucose) in the liver
c) results in elevating blood glucose levels

2) secreted by beta cells
3) functions
a) stimulates glucose uptake by the liver
b) stimulates glycogen synthesis in the liver and muscle cells
c) results in lowering blood glucose levels

indicated by high blood glucose levels and the presence of glucose in the urine after eating foods rich in glucose

a) sometimes called juvenile diabetes or early-onset diabetes or insulin- dependent diabetes
b) results when not enough insulin is produced, probably resulting from damage to beta cells (typically autoimmune disease during childhood)
c) treatment involves insulin injections

a) sometimes called late-onset diabetes or non- insulin-independent diabetes
b) results when the number of insulin receptors on target cells decline
c) treatment involves weight loss, diet, and exercise

1. found on the tops of the kidneys
2. important in short-term and long-term responses of the body to stress
3. actually composed of two separate glands

1) = inner portion of the adrenal gland
2) secrete catecholamines adrenalin (epinephrine) and noradrenalin (norepinephrine) which prepare the body for it's flight-or-fight response
3) these hormones also function as neurotransmitters in the nervous system

1) the outer layer
2) hormones
a) glucocorticoids (e.g., cortisol)
b) mineralcorticoids (e.g., aldosterone) 
c) sex steroids

1) stimulate glucose production for energy metabolism
2) pharmacological doses inhibit inflammation

involved with maintaining electrolyte balances and influencing water conservation by the body

hormones identical to sex hormones produced by the testes and ovaries

a. produce androgens (e.g., testosterone)
b. hormones important in the development and maintenance of the male reproductive system
c. also influence male secondary sex characteristics

a. produce estrogens (e.g., estradiol)
b. hormones important in the development and maintenance of the female reproductive system
c. also influence female secondary sex characteristics

1. found in the mediastinum
2. secretes thymosin

1. atrial natriuretic hormone (ANH)
2. secreted by the wall of the atrium of the heart

1. functions as an endocrine gland during pregnancy
2. hormones
a. chorionic gonadotropin
b. estrogen
c. progesterone