PHGY 216 Exam Study Guide –
Practice Questions with
Answers. Updated 2026
glands
form coordinated system & secrete hormones
but not structurally connected
endocrine system
regulatory system of the body
produces hormones for homeostatic adjustments & other functions
main functions of endocrine system
maintain constant internal environment via regulation of metabolism &
H20/electrolyte balance
2. adaptive stress response
3. growth & development
4. reproduction
5. red blood cell production
6. integrating with ANS in regulating circulation & digestive functions
hormones
secreted directly into blood at low quantities
excrete physiological effect at distant target tissue
types: hydrophilic & lipophilic
hydrophilic hormones
,water-soluble & low lipid solubility
unbound to carrier molecule in plasma
are peptide hormones - peptides (short aa chain) or proteins (long aa chain)
OR amines - of single aa (catecholamines & thyroid
peptide hormone synthesis
1. synthesis - preprohormones (precursor) made
2. packaging - precursor is processed into active hormones & packaged into
secretory vesicles
3. storage - vesicles stored until signal
4. secretion - vesicle exocytosis with signal to bind
lipophilic hormones
lipid-soluble & low water solubility
need carrier molecules for transport throughout the body
include: thyroid & steroid hormones
steroid hormone synthesis
from cholesterol - depends on enzymes in tissue & are released upon synthesis
(bc lipophilic), so control synthesis
target cells & hydrophilic hormones
easy to interact with target cell
target cells & lipophilic hormones
need carrier molecules
hormones are binding & rebinding so little bit of hormone is always unbound
unbound hormone is active & can act on target cells
hydrophilic hormones & cell receptors
bind to receptors on outer surface
bc can't cross cell membrane
lipophilic hormones & cell receptors
bind to receptors inside target cells
when peptide hormones & catecholamines bind receptors
,activated 2nd messenger systems - amplify signals, as low [hormone] trigger
pronounced cellular responses
cAMP or Ca2+
when lipophilic hormones bind receptors
binding of hormones to receptors regulates gene transcription & protein
syntehsis
steps of lipophilic hormones affect cells by regulating protein synthesis
1. free lipophilic hormone diffuse across plasma membrane &/or nuclear
membrane to interact with intracellular receptors
2. hormone-receptor complex binds to hormone response element
within DNA
3. DNA binding activates specific genes & produces mRNA
4. mRNA leaves nucleus
5. mRNA binds to a ribosome & proteins are synthesized
6. newly synthesized proteins ultimately lead to cellular response of hormone
response time
nervous control - rapid response (msecs)
endocrine control - slow responses (mins to hrs)
duration of effects
nervous control: brief (ends when stimulus stops)
endocrine control: long (effects persist after stimulus stops)
number of targets
nervous control: hard-wired to 1 specific target (muscle or gland)
endocrine control: many diff targets in body (blood circulates)
pituitary gland
in bony cavity at base of skull
2 lobes: posterior (neural-like tissue, neurohypophysis) & anterior (of glandular
epithelial tissue, adenohypophysis)
pituitary hormone release
, controlled by hypothalamus
posterior pituitary hormone release
connected to hypothalamus by neural pathways
neuron clusters in hypothalamus (supraoptic & paraventricular nucleus) have
axons that project down to pituitary stalk & terminate on blood vessels in
posterior pituitary
anterior pituitary hormone release
connected to hypothalamus by hypothalamic-hypophyseal portal system
hypothalamus secretes hormones into this portal system & they're carried
directly to anterior pituitary to promote or inhibit release of anterior pituitary
hormones
hormones of posterior pituitary gland
synthesized in neuron cell bodies of hypothalamus then packaged into vesicles
which are transported down axons to nerve endings in posterior pituitary
when stimulus reaches hypothalamus - neurons transport AP that causes
release of hormone containing vesicles into blood
vasopressin & oxytocin
vasopressin
2 major actions: enhancing retention of H2O by kidneys & causes contraction
of arteriolar smooth muscle
ex. antidiuretic hormone (ADH)
oxytocin
2 major roles: stimulating contraction of uterine smooth muscle cells during
childbirth & promoting milk ejection during breastfeedingg
hormones of anterior pituitary gland
synthesizes & releases 6 hormones - all peptides
hormones synthesize in specific cell populations
topic hormones
Practice Questions with
Answers. Updated 2026
glands
form coordinated system & secrete hormones
but not structurally connected
endocrine system
regulatory system of the body
produces hormones for homeostatic adjustments & other functions
main functions of endocrine system
maintain constant internal environment via regulation of metabolism &
H20/electrolyte balance
2. adaptive stress response
3. growth & development
4. reproduction
5. red blood cell production
6. integrating with ANS in regulating circulation & digestive functions
hormones
secreted directly into blood at low quantities
excrete physiological effect at distant target tissue
types: hydrophilic & lipophilic
hydrophilic hormones
,water-soluble & low lipid solubility
unbound to carrier molecule in plasma
are peptide hormones - peptides (short aa chain) or proteins (long aa chain)
OR amines - of single aa (catecholamines & thyroid
peptide hormone synthesis
1. synthesis - preprohormones (precursor) made
2. packaging - precursor is processed into active hormones & packaged into
secretory vesicles
3. storage - vesicles stored until signal
4. secretion - vesicle exocytosis with signal to bind
lipophilic hormones
lipid-soluble & low water solubility
need carrier molecules for transport throughout the body
include: thyroid & steroid hormones
steroid hormone synthesis
from cholesterol - depends on enzymes in tissue & are released upon synthesis
(bc lipophilic), so control synthesis
target cells & hydrophilic hormones
easy to interact with target cell
target cells & lipophilic hormones
need carrier molecules
hormones are binding & rebinding so little bit of hormone is always unbound
unbound hormone is active & can act on target cells
hydrophilic hormones & cell receptors
bind to receptors on outer surface
bc can't cross cell membrane
lipophilic hormones & cell receptors
bind to receptors inside target cells
when peptide hormones & catecholamines bind receptors
,activated 2nd messenger systems - amplify signals, as low [hormone] trigger
pronounced cellular responses
cAMP or Ca2+
when lipophilic hormones bind receptors
binding of hormones to receptors regulates gene transcription & protein
syntehsis
steps of lipophilic hormones affect cells by regulating protein synthesis
1. free lipophilic hormone diffuse across plasma membrane &/or nuclear
membrane to interact with intracellular receptors
2. hormone-receptor complex binds to hormone response element
within DNA
3. DNA binding activates specific genes & produces mRNA
4. mRNA leaves nucleus
5. mRNA binds to a ribosome & proteins are synthesized
6. newly synthesized proteins ultimately lead to cellular response of hormone
response time
nervous control - rapid response (msecs)
endocrine control - slow responses (mins to hrs)
duration of effects
nervous control: brief (ends when stimulus stops)
endocrine control: long (effects persist after stimulus stops)
number of targets
nervous control: hard-wired to 1 specific target (muscle or gland)
endocrine control: many diff targets in body (blood circulates)
pituitary gland
in bony cavity at base of skull
2 lobes: posterior (neural-like tissue, neurohypophysis) & anterior (of glandular
epithelial tissue, adenohypophysis)
pituitary hormone release
, controlled by hypothalamus
posterior pituitary hormone release
connected to hypothalamus by neural pathways
neuron clusters in hypothalamus (supraoptic & paraventricular nucleus) have
axons that project down to pituitary stalk & terminate on blood vessels in
posterior pituitary
anterior pituitary hormone release
connected to hypothalamus by hypothalamic-hypophyseal portal system
hypothalamus secretes hormones into this portal system & they're carried
directly to anterior pituitary to promote or inhibit release of anterior pituitary
hormones
hormones of posterior pituitary gland
synthesized in neuron cell bodies of hypothalamus then packaged into vesicles
which are transported down axons to nerve endings in posterior pituitary
when stimulus reaches hypothalamus - neurons transport AP that causes
release of hormone containing vesicles into blood
vasopressin & oxytocin
vasopressin
2 major actions: enhancing retention of H2O by kidneys & causes contraction
of arteriolar smooth muscle
ex. antidiuretic hormone (ADH)
oxytocin
2 major roles: stimulating contraction of uterine smooth muscle cells during
childbirth & promoting milk ejection during breastfeedingg
hormones of anterior pituitary gland
synthesizes & releases 6 hormones - all peptides
hormones synthesize in specific cell populations
topic hormones
