endocrine system 1 Flashcards
nervous system vs endocrine system
nervous
- communicates via AP and release of NT
- extremely rapid (less than a sec)
- frequency
- neurons going to a specific site
endocrine system
-communicates via hormones into the blood stream
-slow ( minutes hours days)
-amplitude modulation
-receptor specificity (hormone will only bind to that spot)
tissues and cells capable of secreting and responding to hormones
endocrine system overview
includes endocrine glands that secret hormones and hormone secreting cells located in various organs
endocrine vs exocrine
endocrine glands are DUCTLESS and release hormones into the blood (this class)
exocrine glands secrete their products into a duct, then either exit body or enter lumen/another organ (can be duct or ductless) (more 132)
hormones
chemical messengers that are formed in one organ or part of the body and carried in the blood to another organ or part
- target cells
- can alter the functional activity of just one organ or of various numbers of them
- heavily depends on target receptors and target cells
3 classes of hormones
peptide/protein
steroid
amine
hypothalamus
considered part of endocrine system
-portal system or blood system that connects hypothalamus to anterior pituitary gland
anterior pituitary gland
produces hormones with diverse actions related to metabolism, reproduction, growth and others
-ACTH, FSH, LH, GH, PRL, TSH
HPA axis
interaction between hypothalamus-pituitary gland and adrenal gland
a single gland can secrete
a single cell type can secrete
single gland can secrete multiple hormones
single cell types can secret only one hormone**
hormones can be secreted by certain endocrine glands but also other cell type and serve in these other locations as NT’s, paracrine or autocrine substances
paracrine activation hormone vs autocrine
paracrine hormone is released to cell adjacent to the cell that is releasing
autocrine is releasing itself
amine hormones derivatives of what
amino acid tyrosine
amine hormones water soluble?
are water soluble
examples of amine hormones
- thyroid hormones (produced by thyroid gland)
- epinephrine and norepinephrine (produced by adrenal medulla)
- dopamine (produced by hypothalamus)
thyroid hormones produced by what? where
produced by thyroid gland on trachea
-just above the sternum
epinephrine and norepinephrine produced by ? where? which hormone is secreted more?
adrenal medulla
sits on top of kidney, medulla middle
- epinephrine is secreted 4x more than norepinephrine
- it is secreted more because it eventually gets converted to norepi by PMMT?