Physio Exam 3 Chapter 11 Part 1 Flashcards
Do endocrine glands lack ducts?
yes
Specialized neurons that secrete chemicals into the blood rather than synaptic cleft.
The chemical they secrete is called?
neurohormone (NE and asopresin are examples of neurohormone)
Affect metabolism of target organs.
Help regulate total body metabolism, growth, and reproduction, these are called?
hormones
NE, Epi and T4 (Tyroxine) are hormones derived from _____ and _____, they are called amines.
tyrosine and tryptophan
Protein hormones: polypeptide chain with > 100 amino acids, an example of a protein hormone would be?
growth hormone
Lipophilic hormones are lipids derived from cholesterol, some examples would be (4 of them)
testerone, estradiol, coritsol and progesterone
Glycoproteins, long polypepties (>100) bound to 1 or more carbohydrate, some examples would be… (2 of them)
FSH and LH
Pinel gland secretes ______, has properties of both water soluble and lipophilic hormones
melatonin
Nonpolar (lipophilic) hormones can ________ into target cell. Examples would be steroid hormones and _______
gain entry, T4
Precursor is a longer chained polypeptide that is cut and spliced together to make the hormone is…..
Prohormone derived from larger precursor molecule….
Molecules secreted by endocrine glands that are inactive until changed into hormones by target cells….
prohormone, preprohormone, prehormone
APs are chemical events produced by ______ of ions through _________ membrane
diffusion, neuron plasma
Action of some hormones are accompanied by ion diffusion and electrical changes in the target cell.
Nerve axon boutons release_____.
Some chemicals are secreted as _______, and also are________.
NTs, hormones, NTs
In order for either a NT or hormone to function in physiological regulation:
Target cell must have specific _________.
Combination of the regulatory molecule with its receptor proteins must cause a specific sequence of changes.
There must be a mechanism to quickly _______ the action of a ______.
receptor proteins, turn off, receptor
Two hormones work together to produce a result.
synergistic
Each hormone separately produces response, together at same concentrations stimulate even greater effect.
NE and Epi
additive hormonal interaction
Each hormone stimulates different step in the process.
FSH and testosterone
complementary hormonal interaction
Hormone enhances the responsiveness of a target organ to second hormone.
Increases the activity of a second hormone.
Prior exposure of uterus to estrogen induces formation of receptors for progesterone
permissive effects
Action of one hormone _______the effect of another. Insulin and glucagon
antagonistic effect
Hormone in blood reflects the rate of _____. Varying hormone within normal, physiological range can affect the_______ of target cells.
secretion, responsiveness
Increase number of receptors formed on target cells in response to particular hormone.
Greater response by the target cell
priming effect (upregulation)
Prolonged exposure to high [polypeptide hormone]. This is called?
Subsequent exposure to the same [hormone] produces less response.
Decrease in number of receptors on target cells, an example of this would be
desensitization (downregulation) insulin in adipose cells
Pulsatile secretion may prevent?
downregulation
In regards to mechanisms of hormone action, hormones exhibit these 2 main things?
affinity and saturation
Lipophilic steroid and thyroid hormones are attached to plasma carrier proteins because they are……
Hormones dissociate from carrier proteins to pass through ________ of the target plasma membrane
not water soluble, lipid component
Receptors for the lipophilic hormones are know as…..
nuclear hormone receptors
Steroid receptors are located in ______ and in the ______ of a cell?
cytoplasm and nucleus
Nuclear hormone receptors function within cell to activate….
Messenger RNA directs synthesis of specific enzyme proteins that change metabolism
genetic transcription
Each nuclear hormone receptor has 2 regions………
Ligand binding domain and DNA binding domain
In regards to nuclear hormone receptors, receptor must be activated by binding to ______ before binding to specific region of DNA called ________
Located adjacent to gene that will be transcribed
hormone, HRE (Hormone Responsive Element)
Mechanism of steroid hormone action, cytoplasmic receptor binds to _________. This translocates to the ________. DNA binding domain binds to specific ________ of the DNA.
hormone, nucleus, HRE
For mechanisms of steroid hormone action, after DNA binding domain binds to specific HRE of the DNA this occurs? Which is the process of 2 receptor units coming together at the 2 half site. This stimulates ________ of particular genes.
dimerazation, transcription
For thyroid hormone, T4 passes into cytoplasm and becomes? This hormone binds to what domain?
T3, ligand binding domain
What vitamin is involved with mechanism of thyroid hormone action?
Vitamin A
What two partners bind to the DNA to activate HRE in thyroid hormone action? This stimulates transcription of genes
T3 and Vitamin A (9-cis-retinoic acid)
Hormones cannot pass through plasma membrane use _______?
2nd messengers
Polypeptide or glycoprotein hormone binds to receptor protein causing dissociation of a subunit of______?
This subunit binds to and activates _______. ATP—cAMP and PPi
G protein, adenylate cyclase
cAMP attaches to inhibitory subunit of……., this inhibitory subunit disscoiates and activates this protein as well
protein kinase
cAMP is inactivated by…….., it hydrolyzes cAMP to inactive fragments
phosphodiesterase
Adeylate Cyclase-cAMP phosphorylates enzymes within the cell to produces________. It modulates the activity of _______ present in the cell and alter the metabolism of the cell.
hormone’s effect, enzymes
Binding of Epi to a-adrenergic receptor in plasma membrane activates a G-protein intermediate….
phospholipase C
Phospholipase C splits phospholipid into ____ and _____. Both are derivatives of 2nd messengers.
IP3 and DAG
IP3 diffuses through cytoplasm to RE. Binding of IP3 to receptor protein in ER causes ______channels to open?
CA2+
In Phospholipase, CA2+ diffuses into the cytoplasm where it binds to…..
calmodulin
Calmodulin activates specific protein kinase enzymes, altering the _____ of the cell, producing the _______.
metabolism, hormone’s effect
Insulin receptor consists of 2 units that dimerize when they bind with insulin.
tyrosine kinase
In tyrosine kinase, insulin binds to _________ site on plasma membrane, activating enzymatic site in the _______.
ligand binding site, cytoplasm
What increases tyrosine kinase activity? This activates signaling molecules, stimulating glyocogen, fat and protein synthesis.
autophosphorylation
The pituitary gland is located in the diencephalon (true or false) how many lobes does it have?
true and 2 (anterior/posterior)
Anterior pituitary has trophic effects: high blood hormone causes target organ to ______. Low blood hormone causes target organ to ______?
hypertrophy, atrophy
Posterior pituitary stores and releases 2 hormones and are produced in the hypothalamus, what are they?
ADH and Oxytocin
ADH promotes retention of ______ by the _______. Less ______ is excreted in the ______.
H2O, kidneys, H2O, urine
Oxytocin stimulates contractions of the ______ during parturition. Stimulates contractions of the mammary gland ______, this is the milk ejection reflex.
uterus, alveoli
