Exam 1 (Chapter 7) Flashcards
what do hormones act on?
target cels
what (3) things do hormones do?
-alter rates of enzymatic rxns
-alter transport of ions/molecules across cell membrane
-alter gene expression & protein synthesis
what is goiter?
swelling of the thyroid gland
-due to an excess of the thyroid hormones
what are (3) steps on how to identify the gland & hormone?
1) remove suspect gland
2) replace the hormone (gland extract)
3) create hormone excess
what is different about pheromones in relation to being a hormone?
they are secreted into the external environment
-not by blood like a normal hormone
what is different about cytokines in relation to being a hormone?
they are made on demand
-not stored
what are candidate hormones?
hormones that appear to look/act like a hormone but are a little bit different
-end in “factor”
what are (3) ways you can terminate a hormone?
-limit secretion of hormone
-remove / inactive hormone (enzymes)
-terminate action at the cell (remove receptor, alter pathway)
what does half-life indicate when referring to a hormone? what does it mean to have a short half life?
indicates length of activity and time it takes do reduce conc.
-short 1/2 life = short activity time, quick removal of hormone
what are (3) ways hormones are classified?
-source of hormone
-if release controlled by brain or not
-receptor type they bind to
what are the (3) main chemical classes of hormones?
-peptide/protein hormone
-steroid hormone
-amine hormone
what is required for peptide/protein hormone synthesis?
ribosomes, rough ER, golgi
-preprohormone, prohormone
how is a preprohormone made into prohormone? how is it made into an active hormone?
-preprohormone is shuttled to the rough ER
-sequence is trimmed to make the prohormone
-prohormone is sent to the golgi to be stored in a vesicle
-enzyme inside vesicle cuts & processes it to make the active hormone
how is a peptide/protein hormone released?
-signal is sent to vesicle
-vesicle moves & fuses with plasma membrane
-exocytosis of vesicle to release hormone
how are peptide/protein hormones transported in the blood? (philic or phobic?)
hydroPHILIC / lipoPHOBIC
-can dissolve in plasma
-NO transport protein needed
what type of receptor do peptide/protein hormones use? what mechanism of action is it?
surface receptors
-2nd messenger systems (G-protein, receptor kinases)
do peptide/protein hormones have a fast or slow response? is the half life short or long?
fast response
short 1/2 life
what is required for steroid hormone synthesis? where is it made?
cholesterol
-made in smooth ER
how are steroid hormones stored and released?
NOT STORED
-made on demand
-released through simple diffusion
are steroid hormones hydrophilic or hydrophobic?
hydroPHOBIC / lipoPHILIC
how are steroid hormones transported in the blood?
they require a transport protein
-plasma proteins (makes it water soluble)
what type of receptors do steroid hormones use?
intracellular receptors
-on the cytoplasm or nucleus
what is the mechanism of action of steroid hormones?
alter gene expression
do steroid hormones have a fast or slow response? is the half life short or long?
slow response
-long 1/2 life