Flashcard Set Preview
Side ASide B
What are peptide hormones?
lipophobic hormones that contain copies of the hormone and a signal sequence...
What does it mean if a hormone is lipophobic?
it dissolves easily in extracellular fluidunable to enter target cells
What are steroid hormones derived from?
Where are steroid hormones produced?
gonads, placenta, cortex of adrenal gland
Are steroid hormones soluble in plasma?
no, they are lipopphyllic.most steroid hormones found in the blood are bound...
What do gonads produce?
What is the mechanism of signal transduction for peptide hormones?
the bind to the cell surface receptors because they cannot enter the cell otherwise.GPCR...
Why is cell response to peptide hormones rapid?
because second messenger systems modify existing proteins.
What is a preprohormone?
mRNA on the ribosome binds amino acids into a peptide chaininactivepeptide hormone synthesis
What is a prohormone?
enzymes in the ER chop off the signal sequence creating an inactive prohormone.inactivebecomes...
What is protranslational modification?
when prolytic enzymes chop the prohormone into active hormone and other...
What is an echtohormone?
a hormone secreted by a cell to the external environmentex: pheremones
What makes a chemical a hormone?
it is secreted by a cell or group of cells into the blood or external environmentexerts it's...
What is a catecholamine?
fight or flight hormonesreleased by the adrenal glands in response to stresspart of...
What is acetylcholinesterase?
degrades acetylcholineterminates synaptic transmission
What type of cells in steriod hormone synthesis can diffuse to target cells?
only unbound hormones can diffuse to target cells
What is a signal sequence?
in peptide hormone synthesis; directs the preprohormone into the RER lumen by...
Describe peptide hormone synthesis.
(1) comes off ribosome as a preprohormone containing 1 or more copies of the peptide...
Which hormones are lipophilic?
Which hormones are lipophobic?
Describe quickly peptide hormone synthesis
ribosome --> preprohormone --> signal sequence --> prohormone --> prohormone activating...
What is negative feedback?
a pathway in which the response opposes or removes the signal.
The pancreas releases which hormones? What is the main effect of these hormones?
releases: insulin glucagon ...
Where are steroid hormones synthesized? How often are they synthesized?
in the smooth ERsteroid hormones are only synthesized as needed as they cannot...
How are steroid hormones converted to active hormone?
actively and quicklyhormone concentration in the cytoplasm rises and hormones move out...
How is the half life of steroid hormones extended?
the binding of steriod hormones to a carrier protein extends the half life by protecting...
Where are receptors for steriod hormones found?
cytoplasm or nucleus
What is the transcription factor of steroid hormones? What is the effect...
binds to DNA, activating or repressing on or more genesactivating new genes creates new mRNA...
How are peptide hormones released from parent cells?
Describe the half life of peptide hormones.
short half life
What is the target response to peptide hormones?
modification of existing proteins & the induction of new protein synthesis
Give two examples of peptide hormones.
insulin parathyroid hormone
Which hormones are made in advance and stored in secretory vesicles?
Give three examples of steroid hormones. Where are they produced?
estrogen, cortisol, androgensthe endocrine cells of gonads produce these hormones
What synthesizes and secretes steroid hormones?
the adrenal cortex
How are hormones classified?
by source, receptor, and chemical structure.
What is the key feature of hormonal cascade?
How does the hormonal cascade proceed?
stimulus --> hypothalamus releases hypophysio-trophic hormone --> anterior pituitary...
Specifically, what hormones does the adrenal cortex synthesis and release?
(1) aldosterone (mineralcorticoids)(2) androgens (sex hormones) ...
What is cortisol? What does it have the ability to do?
the main glucocorticoid secreted by the adrenal cortex. It has the ability to...
What is a trophic hormone?
a hormone made and released by the anterior pituitary and target endocrine glands.
What is the adrenal cortex tropic hormone? (ACTH)
a peptide hormonestimulates the adrenal cortex to release glucocorticoids
What is the target of ACTH? What does it do?
steroidogenic cells of the adrenal cortexstimulates the synthesis and release of glucocorticoids....
What are the three types of hormone interaction?
synergistic, permissive, and antagonistic interactions
a hormonal interaction where two hormones together produce a greater effect than the sum...
Give an example of synergism.
Potentiation- "epinepherine potentiates glucagon's effect on blood glucose levels."
Describe permissive interactions.
a hormonal interaction where one hormone cannot fully exert its effect unless a second hormone...
Give an example of a permissive interaction.
because thyroid hormone by itself cannot stimulate maturation of the reproductive system, thyroid...
Describe antagonistic interactions.
when two hormones work against eachother, sometimes one diminishes the effectiveness of the...
Give an example of an antagonistic hormone interaction.
Growth hormone decreases the number of insulin receptors
What is a functional antagonist? Give an example.
when two hormones have opposing physiological actions.Ex: growth hormone increases glucose...
The pituitary is composed of how many glands?
two fused glands- anterior and posterior
What is the anterior pituitary gland? What controls the secretion of these hormones?
endocrine gland that secretes 6 hormones.secretion is controlled by the hypothalamic...
Name the hormones secreted by the anterior pituitary and their abbreviations.
1. Prolactin (PRL)2. Thyrotropin (TSH)3. Adrenocorticotropin (ACTH)4....
What is the target of the hormone PRL?
prolactic; breast/mammary glands
What is the target of the hormone TSH?
thyrotropin; thyroid gland further initiates release of--> thyroid hormones...
What is the target of the hormone ACTH?
adrenocorticotropin; adrenal cortexfurther initiates release of--> cortisol...
What is the target of the hormone GH?
growth hormone; musculoskeletal system & liverfurther initiates the release...
What is the target of the hormone FSH and LH?
Follicle stimulating hormone and Lutenizing hormone; endocrine cells of the gonadsfurther...
What is the posterior pituitary?
the storage and release site for 2 neurohormones- vasopressin (ADH) and oxytocin
Where are the hormones of the posterior pituitary made and packaged?
in the cell body of neurons in the hypothalamus
Describe the synthesis, storage, and release of posterior pituitary hormones.
(1) hormone is made & packaged in the cell body of neurons in the hypothalamus.(2) vesicles...
Describe the synthesis, storage, and release of anterior pituitary hormones.
(1) neurons synthesizing trophic hormones release ant. pit. hormones from the hypothalamus...
What is vasopressin? Where is it stored and released?
(ADH) antiduirectic hormoneregulates water balance in the bodyconsists of 9 amino acidsstored...
What is oxytocin? Where is it stored and released?
control the ejection of milk during breast feeding and contractions of the uterus during labor.stored...
What is a reflex pathway?
stimulus, input signal, integration of the signal, an output signal, and a response.
What is a simple reflex pathway. Give an example.
The response of the pathway serves as the negative feedback signal that turns off the reflux.increase...