Bio 225 Exam 1 - Endocrine System - Lloyd

UofM Biology 225 Exam 1 - Endocrine System

Types of cell signaling

autocrine/paracrine, nervous, endocrine, direct cell signaling (inter-individual)

Secretory cell, target cell, signal type, max. signaling distance, transport b/w cells, speed, and duration of response for autocrine/paracrine cell signaling

various; various; chemical; short; interstitial fluid; rapid; short

Secretory cell, target cell, signal type, max. signaling distance, transport b/w cells, speed, and duration of response for nervous cell signaling

neural; neuron, muscle, adipose, endocrine, exocrine; electrical and chemical; can be long intracellularly, short across synapse; synapse; rapid; short

Secretory cell, target cell, signal type, max. signaling distance, transport b/w cells, speed, and duration of response for endocrine cell signaling

endocrine; various; chemical; long; circulatory fluids; slower; longer

Secretory cell, target cell, signal type, max. signaling distance, transport b/w cells, speed, and duration of response for inter-individual cell signaling

exocrine and various epithelial cells; sensory and neural; chemical; very long; external environment; various; various

Classes of chemical messengers

peptides (hydrophilic), steroids (hydrophobic), amines (hydrophilic), lipids, purines, gases (we study firsts 3)

hormones are

chemical substances released by one cell which act on another

The ____ of the messenger effects the ______ _______

structure; signaling mechanism

ex: hydrophobicity

Hormones are divided into two different groups based on

hydrophobicity

Hydrophilic messengers (hormones): storage, secretion, transport, receptor, effects

Intracellular vesicles; exocytosis; dissolved in extracellular fluids; transmembrane; rapid

Hydrophobic messengers (hormones): storage, secretion, transport, receptor, effects

synthesized on demand; diffusion across membrane; short distance: dissolved in extracellular fluid, long distances: bound to carrier proteins; intracellular or transmembrane; slower or rapid

Peptide/Protein hormones

hydrophilic; soluble in aqueous solutions; travel to target cell dissolved in extracellular fluid; rapid effects on target cells

Peptide/Protein hormones bind to

transmembrane receptors causing signal transduction

Peptide hormone production and release

Synthesized in RER as preprohormone —> preprohormone cleaved to prohormone —> Golgi apparatus for protein modification and packaging into vesicle —> prohormone in vesicle cleaved into peptide fragment and active hormone —> active hormone released

AVP aka

vasopressin and antidiuretic hormone

Function of AVP

works to control blood pressure by 1) increases H20 reabsorption and 2) constricts arterioles which increases BP

Synthesis and secretion of AVP

RER: arginine vasopressin apart of larger polypeptide as preprovasopressin (includes neurophysin and glycoprotein and signal peptide —> signal peptide cleaved making provasopressin —> leaves RER —> modified packaged by Golgi apparatus into secretory vesicle —> cleavage again into AVP (and glycoprotein and neurophysin)

Secretory vesicles: cleavage again to separate AVP

glycoprotein

protein w/ an oligosaccharide side chain

neurophysin

carrier protein for oxytocin and vasopressin

Amine hormones are

hormones that possess amine group (-NH2)

most hydrophilic (thyroid hormones are hydrophobic)

examples of amine hormones

acetylcholine, catecholamines (dopamine, norepinephrine, epinephrine), serotonin, melatonin, histamine, thyroid hormones

amine hormones are sometimes called and naming

biogenic amines

end in -ine

amine hormones are what kind of hormones

some”true” (endocrine) hormones, some neurotransmitters, some both

amine hormones have

diverse effects

Steroid hormones are derived from

cholesterol (three 6-C rings and one 5-C ring)

Steroid hormone examples

pregnenolone, progesterone (cortisol, testosterone, corticosterone —> aldosterone)

3 classes of steroid hormones

mineralocorticoids, glucocorticoides, reproductive hormones

steroid hormones synthesized by

smooth ER or mitochondria

steroid hormone naming

end in -one

Mineralocorticoids

electrolyte balance (water ion balance)

glucocorticoides

stress hormones

reproductive hormones

reglate sex-specific characteristics

Steroid hormones

hydrophobic (can diffuse thru plasma membrane)

cannot be stored in cell; must be synthesized on demand

Steroid hormones pathway

synthesized on demand —> the chemical messenger binds to carrier proteins (most not all) —> circulatory system carries the free and bound messenger to target cell —> free messenger binds to intracellular or transmembrane receptors (usually intracellular)

steroid hormone effect speed

slow effects on target cell (gene transcription)

stress hormone cortisol has rapid non-genomic effects