Chapter 10 Endocrine System Flashcards
endocrine
secretes its product into the blood
exocrine
secretes its product onto a body surface
hormone
Chemical messenger released by one tissue into blood, then transported to target cells in other tissues
Target
cells that have the receptor for the hormone and can “read” the message
-Statin
regulatory hormone that inhibits release of another hormone
-tropin
regulatory hormone that “turns on” another endocrine gland or supports the function of another organ
functions of the endocrine system
- tells your body what homeostasis is and makes it happen
- metabolism: for all organ systems, adjusts metabolic rate and use of substances, such as glucose, triglycerides, and amino acids
- regulates growth and development
Amino acid derivative
the hormone is made by modifying an amino acid.
Ex: melatonin, Thyroid hormone, Epinephrine (adrenaline), Norepinephrine (in neurons)
Peptide hormones
Made of chains of amino acids.
- The short chains, such as oxytocin and antidiuretic hormone are called POLYPEPTIDE hormones
- the long chains, including everything made by the hypothalamus, pituitary gland, kidneys, hear thymus digestive tract and pancreas, are called PROTEIN hormones
- most hormones are PROTIEN hormones
lipid derivatives
lipid based hormones.
- receptors are in the nucleolus, not in the plasma membrane
two types of lipid derivatives
steroid hormones: based on CHOLESTEROL. Made by reproductive organs and adrenal glands
- eicosanoids: fatty acid based Ex: prostaglandins
Antidiuretic hormone (ADH)
acts on kidneys to decrease amount of water lost in urine, keeps you from peeing
Oxytocin
stimulates labor contractions, release of breast milk, and possibly affects smooth muscle contraction of relevant tubes during sexual intercourse
Where is the hypothalamus located
below the thalamus
- part of the dicephalon which is part of the nervous system
what 2 hormones does the hypothalamus secrete into the whole body
- Anitdiuretic hormone
- oxytocin
- both are secreted by the pituitary gland
another name for the hypothalamus
the master of master glands
what is the hypothlamo-hypophyseal portal system
a portal system is a blood flow that takes all of the hormone to the target cells before anything else can see the hormone. Hypothalamic regulatory hormones go straight to the pituitary gland
What are the two classes of hormones that the hypothalamus releases
Releasing hormones: tell the anterior thyroid to release one of its hormones
inhibiting hormones: tell the anterior thyroid not to release one of its hormones
How does the hypo thalamus control with the adrenal medullae?
it controls the sympathetic output to the adrenal medullae and controls how much SNS stimuli they get
adrenal medullae (center)
secrete their hormones when the SNS is activated
location of the pituitary gland
located in the sella turcica: the saddle-shaped depression in the interior of the sphenoid bone
name the 2 parts of the pituitary gland
Anterior pituitary
posterior pituitary
Anterior pituitary
- made of glandular tissue: in its own gland
- secretes
- THYROID-STIMULATING hormone (TSH) - ADRENOCORTICOTROPIC hormone (ADH),
- FOLLICLE-STIMULATING hormone (FSH),
- LUTEINIZING hormone (LH),
- PROLACTIN,
- GROWTH hormone
- MELANOCYTE- STIMULATING hormone
Posterior Pituitary
Contains axons from the hypothalamus
- secretes ADH and Oxytocin
Thyroid-stimulating hormone (TSH)
Triggers the release of thyroid hormones
- Part of the Anterior pituitary
Adrenocorticotropic hormone (ACTH)
stimulates the outer layer of the adrenal glands to secrete special steroid hormones called glucocorticoids, which regulate glucose metabolism
- Part of the Anterior pituitary
Follicle-stimulating hormone (FSH)
promotes follicle development in the ovaries and stimulates the secretions of estrogen, also supports sperm production
- promotes formation of ova and sperm
- Part of the Anterior pituitary
luteinizing hormone (LH)
Induces ovulation, also stimulates secretion of estrogen and progesterone to prepare for a possible pregnancy,
- in males, it stimulates androgen production (testosterone)
- Part of the Anterior pituitary
prolactin
Helps to stimulate mammary gland development. Stimulates breast milk production.
- Part of the Anterior pituitary
Growth hormone
Stimulates cell growth and replication by speeding up the rate of protein synthesis.
- skeletal muscle cells and chondrocytes are particularly susceptible to GH
- Part of the Anterior pituitary
2 ways growth hormones speed up growing process
indirect
Direct
Growth hormone: indirect
indirect: tells the liver cells to make insulin-like growth factors, which stimulate increased protein synthesis in a variety of tissues
growth hormone: direct
Direct: stimulates division of stems cells and differentiation of daughter cells. Also tells cells to break down fatty acids and break down glycogen instead of just using their glucose stores
Melanocyte-stimulating hormone
Stimulates the melanocytes in the skin to increase their production of melanin.
Hyothalamo-hypophyseal TRACT;
1- Starts in the hypothalamus
2- ends in the POSTERIOR pituitary gland
3- made of nerve axons
4- the hormones transported are the posterior pituitary hormones, OXYTOCIN and ADH
what is the hypophyseal
old name for the pituitary gland
Hypothalamo-Hypophyseal PORTAL system
1- Made of capillary (blood vessels) network that runs from the hypothalamus through the infundibulum [stalk] connecting it to the pituitary
2- ends in the anterior pituitary gland
3- transports all regulatory hormones
4- deals with blood
Regulatory hormones
- THYROTORPIN-RELEASING hormone
- CORTOCOTROPIN-RELEASING hormone
- GONADOTROPIN-RELEASIGN hormone
- PROLACTIN RELEASONG factor
- PROLACTIN-INHIBITING hormone
- GROWTH hormone
Thyrotropin-releasing hormone
- Regulatory hormone
- stimulates release of TSH
- also known as thyrotropin
- turns on the thyroid gland
corticotropin-releasing hormone
- regulatory hormone
- stimulates the release of ACTH (Adrenocorticotropic hormone)
gonadotropin releasing hormone
stimulates the release of FSH (Follicle-stimulating hormone) and LH (luteinizing hormone)
prolactin-releasing factor
stimulates release of prolactin
prolactin-inhibiting hormone
inhibits release of prolactin
Growth regulatory Hormone
has both releasing and inhibiting hormones
Thyroid gland: location
Anterior neck, inferior to “adams apple” its on the anterior surface of the larynx
thyroid gland: structure
*Second true endocrine organ
left and right lobes are connected by an isthmus. This is so it fits on the neck
- each lobe functions the same way.
pituitary gland
master gland
* first true endocrine organ
Calcitonon
thyroid gland hormone
- Calcitonin cells, are squished between this epithelium and the basement membrane of the thyroid tissue
- Helps regulate calcium ion concentrations in body fluids.
- ONLY IMPORTANT IN CHILDHOOD when it stimulates active bone growth and calcium deposition in the skeleton
-
Parathyroid Glands
- third true endocrine organ
- 4 tiny oval glands located behind the thyroid
Parathyroid hormone
goal is to get more calcium in the blood
- activates osteoclasts and inhibits osteoblasts.
- tells kidneys to stop urinating calcium
- tells kidneys to secrete calcitriol to tell the digestive system to absorb more calcium
Adrenal glands
- fourth true endocrine organ
- location: on the kidneys
- 2 yellow pyramid shaped glands
Adrenal glands
- fourth true endocrine organ
- location: on the kidneys
- 2 yellow pyramid shaped glands
two layers of the adrenal gland
Adrenal cortex (outer part) adrenal medulla (inner part)
Three part of the adrenal cortex
zona glomerulosa
zona fasciculate
zona reticularis
zona Glomerulosa
SALT!
Produces Aldosterone hormone
- tells the kidneys to reabsorb more SALT
Zona Fasciculata
SUGAR!
makes hormones called GLUCOCORTICOIDS and CORTISOL
- they tell:
- skeletal muscle: release amino acids
- adipose: release lipids
- liver: make more glucose
- tell cells to use fatty acids instead of glucose stores
Zona Reticularis
SEX
produces androgens (sex hormones)
- what stimulates the development of pubic hair before puberty in both sexes
- released before puberty
Adrenal medulla
- produces Epinephrine/adrenaline and norepinephrine
- both increase cardiac activity, blodd pressure, glycogen breakdown, and glucose levels
- get you ready for a fight or flight response
Pineal gland
- the 5th true endocrine organ
- located: in the epithalamus, in the posterior portion of the roof of the third ventricle of the brain
- made of neural cells, glial cells and secretory cells
Pineal gland secretes
Melatonin: which helps regulate your body’s day-night cycle.
- also helps control the timing and release of female reproductive hormones.
- good antioxidant, so it may be neuroprotective and even cardio protective
name the 5 true organs of the endocrine system
pituitary gland thyroid gland parathyroid Adrenal glands pineal gland
endocrine pancreas
- j shaped organ dee in the epigastric region
- 99% of the pancreas is devoted to the making of (exocrine) digestive enzymes
- 1% is dedicated to making to hormones
- insulin
- glucagon
insulin
lowers blood glucose levels
- secreted when glucose is abundant.
- tells cells to use glucose rather than alternate energy source
- gets glucose our of your blood stream
glucagon
increases blood glucose levels
- secrete when blood sugar is low
- tells organs to break things down to create more glucose
hormones made by the kidneys
Calcitriol
Erythropoietin
renin
Calcitriol
Active form of vitamin D
- stimulates absorption of calcium and phosphate by the digestive tract
- secreted in response to parathyroid hormone
Erythropoietin
Kidneys see low oxygen levels in blood and secrete this to the tell the re bone marrow to make fore erythrocytes
renin
secrete this when they see low blood pressure and/or volume
- really an enzyme
- activates another hormone called
- Angiotensin II which stimulates thirst, elevates blood pressure, and tells adrenal glands to make aldosterone
Atrial natriuretic peptide
- made by cardiac muscle cells in the right atrium (1st place heart sees blood returning)
- released when muscles cells are stretched because of too much blood volume
- ANP is the anti-angiotensin II.
- it tells the kidneys to get rid of salt and water
- inhibits renin, ADH, and aldosterone secretion
- decreases blood pressured and volume
Thymus
- The snail shaped organ in the anterior mediastinum
- big in babies, but gets smaller in adults
- an immune organ (where T cells are made) so it’s hormones the thymosins, are involved in the developing and maintaining immune defenses
Testes
make androgens most notably testosterone
Testosterone
promotes production of functional sperm
- determines distribution of facial hair and body fat
- affects protein synthesis and muscle growth, and aggressive behavioral responses
- needed for development of male reproductive organs in the fetus
FSH (Follicle-stimulating hormone) and testes
stimulates testicular growth
- help with sperm production
- stimulates testes to release INHIBIN which regulates sperm production
Estrogen and steroid hormones
- support the maturation of the egg cell and stimulate the growth of the lining of the uterine
Inhibin
does negative feedback in both sexes
progesterone
speeds up the movement of fertilized eggs along the uterine tubes,,
- prepares the uterus for the arrival of an embryo, and causes the mammary glands to enlarge
Leptin
Released by adipose tissue
- reduces suppresses appetite
- leptin is necessary for the development of puberty and fertility
Anatgonistic effects
hormones oppose each other
Ex: insulin and glucagon
Permissive effect
hormone one needs to be present for hormone two to work
ex: epinephrine needs thyroid hormone around to work
synergistic effect
the whole is greate than the sum of its parts–putting tow hormones together produces more bang than the sum of what either would do alone
ex: glucose-sparing effects of growth hormone and glucocorticoids
integrative effect
hormones do different things, but work together to coordinate the activities of diverse physiologic systems
ex: calcitriol and PTH
