unit 5 Flashcards
The endocrine system regulates long-term functions such as ________, _______, _______, and _______
Growth
Metabolism
Regulation of internal environment
Reproduction
Hormones act on target cells by regulating ____, ______, _______
Enzyme activity
Ion transport across membrane
Gene expression
Hormones generated from within are called _______, hormones generated from outside are called _____
Endogenous
Exogenous
Endocrine hormones must travel to target cells through the ______
blood
Three ways to experiment with endocrinology
Lose (ablate)
Replace
Excess
What experiment proved that hormones were not connected to the neurological system?
Remove chicken testes and replace them
Classic hormones vs non-classic hormones
Classic
Secreted into blood, travel to distant targets, act at low concentrations
Non-classic
Not secreted by glands but neurons and immune cells
Act locally, diffusion through ECF
Hormones in one context but can also be secreted in CNS and act as neurotransmitters
There is an equilibrium between _____ and _____ hormones
Free
Bound
3 mechanisms to remove hormones from receptors
Hormones inactivated on their way through liver and kidney
Nonspecific protease break them down
Hormone-receptor complex internalized (endocytosis) by target cell
3 ways to classify hormones
Source
Mechanism of action
Chemistry
Three categories of chemistry of hormones
Peptied/proteins
Amine/ amino acids
steroid
Peptides are _______ and require __________ to sustain a response
Hydrophilic
Continuous release
Peptide hormone synthesis and secretion requires the cell to have lots of _______
Rough ER
The response of peptide hormones is typically ____
Rapid/fast
Amine hormones can come from either _______ or _______
Tryptophan
Tyrosine
Tryptophan amine hormones creates _______ from the ________
Melatonin
Pineal gland
Tyrosine amine hormones can create ________ which are ______ that act via membrane receptors
Catechol amines
Neurohormones
Tyrosine amine hormones can create ________ which are ______ and act via intracellular receptors
Thyroid hormones
Produced by epithelial cells
Steroid hormones are all derived from ______
Cholesterol
Steroids are made in the ______, ______, or ______
Adrenal cortex
Gonads
Placenta
Modifications of cholesterol require _________
Side chain cleavage enzyme
Steroidogenic cells (producing steroids) have large amounts of ______
Smooth ER
Steroids are _______ and ____ stored
Lipophilic
Cannot be
Steroid hormones are typically _________ to help them circulate
Bound to carrier protein or albumin
Steroid receptor proteins are ___________________ that drive gene expression
Ligand activated transcription factors
New proteins made by steroid receptors are typically ___________
Other transcription factors
The pathway of a simple endocrine reflex (6)
Stimulus
Integrating center
Hormone
Target
Tissue response
Systemic response
Adrenal medulla produces ______ by _______ cells
Epinephrine
Chromaffin
The hypothalamus produces _____ in the ________ gland, both ______ and ______
Nurohormones
Pituitary
Posterior
Anterior
The pituitary gland develops from the _________ under the floor of the ________
Rathke’s pouch
Third ventricle
Neuro hypophysis is the ___________, neural
Adeno hypophysis is the _________, glandular
posterior pituitary
anterior pituitary
synergism
combined effect is greater than the sum of individual effects
permissiveness
hormone is required but is not enough for full effect
antagonism
one substance opposes the action of another
hypersecretion can occur due to _______ or _______
tumors of glands
issues with feedback regulation
hyposecretion can occur due to _________ or ________
inability to produce hormone
side effects of exogenous hormones
three ways that can cause an inability to produce hormone
mutations in genes that code for hormones or enzymes that produce the hormones
atrophy of gland due to disease
deficiency in iodine - can’t make thyroid hormones
abnormal responsiveness of target tissues can be caused by _____ or _______
abnormally high hormone levels which then causes down regulation of target cells
mutations in receptor proteins
Posterior pituitary gland creates neurohormone within the ________
Neuron cell body
_____ containing neurohormone are stored in the ____
Vesicles
posterior pituitary
Vasopressin is a ______
Neurohormone
In the anterior pituitary gland the _______ synthesizing neurohormones release them into ________
Neurons
First capillary bed of portal system
____ cells release _____ hormones into second set of capillaries, exit via _________
Endocrine
Peptide
Venous drainage
The target organs of the anterior pituitary gland
My MOAT
MammarY glands
Muscles
Ovaries (and testes)
Adrenal cortex
thyroid
The three tiers of hypothalamic pituitary axis
Hypothalamic hormones
Tropic hormones
Endocrine targets and the hormones they secrete
TRH - ___-___-________
TSH
Thyroid gland
Thyroid hormones (T3, T4)
_____-______-______-Cortisol
CRH
ACTH
Adrenal cortex
_____-____/___-Endocrine cells of the gonads
-______
GnRH
FSH/LH
Androgens/estrogen/progesterone