BIOL 373 4d EXAM Questions with Correct Answers| Latest Update Guaranteed Success
hyperosmolarity higher solute concentration outside the cell (cell shrinks, water leaves cell)
homeostatic responses to salt ingestion vp is released and you feel thirsty
proximal tubule function reabsorbs 70% of water and Na+, iso-osmosis and is always
permeable to water
distal tubule and collecting duct function reabsorbs water via insertion of aquaporins which
is regulate by vp
aldosterone (mineralocorticoid) steroid hormone that is synthesized on demand in the
adrenal cortex acting via intracellular recptors and saves salt while losing potassium
steps of aldosterone action 1. aldosterone from blood binds to cytoplasmic receptor
2. hormone receptor complex = transcription factor --> transcription
3. new protein channels and pumps synthesized
4. aldosterone induced proteins modulate existing channels and pumps
5. results in increased Na+ reabsorption and K+ secretion
stimulation of aldosterone secretion increased plasma concentration of K+ monitored by
cells in the adrenal cortex (protects against hyperkalaemia)
decreased bp involves a complex pathway
, hyperkalemia high potassium in ECF
potassium homeostasis only a small portion of K+ in our bodies is in ECF (cuz its mostly
within our cells) but important to maintain because K+ is a major determinant of resting
membrane potential therefore both hyperkalaemia and hypokalaemia can be fatal
hypokalaemia deficient potassium in the blood
renin angiotensin system (RAS) hormone system that regulates blood pressure and fluid
balance
angiotensinogen a plasma protein produced by the liver
renin enzyme that catalyses angiotensinogen into angiotensin I and is produced by granular
cells in the juxtaglomerular apparatus of the nephron
angiotensin converting enzyme (ACE) enzyme that converts angiotensin I to angiotensin II
angiotensin II 8 amino acid peptide with a short half life and is a potent vasoconstrictor
principal cells receptors for ADH and aldosterone, acts in kidney at distal nephron
RAS pathway 1. angiotensinogen is converted into angiotensin I by renin
2.. angiotensin I is converted to angiotensin II by angiotensin converting enzyme
3. angiotensin II stimulates release of aldosterone from the adrenal cortex
hyperosmolarity higher solute concentration outside the cell (cell shrinks, water leaves cell)
homeostatic responses to salt ingestion vp is released and you feel thirsty
proximal tubule function reabsorbs 70% of water and Na+, iso-osmosis and is always
permeable to water
distal tubule and collecting duct function reabsorbs water via insertion of aquaporins which
is regulate by vp
aldosterone (mineralocorticoid) steroid hormone that is synthesized on demand in the
adrenal cortex acting via intracellular recptors and saves salt while losing potassium
steps of aldosterone action 1. aldosterone from blood binds to cytoplasmic receptor
2. hormone receptor complex = transcription factor --> transcription
3. new protein channels and pumps synthesized
4. aldosterone induced proteins modulate existing channels and pumps
5. results in increased Na+ reabsorption and K+ secretion
stimulation of aldosterone secretion increased plasma concentration of K+ monitored by
cells in the adrenal cortex (protects against hyperkalaemia)
decreased bp involves a complex pathway
, hyperkalemia high potassium in ECF
potassium homeostasis only a small portion of K+ in our bodies is in ECF (cuz its mostly
within our cells) but important to maintain because K+ is a major determinant of resting
membrane potential therefore both hyperkalaemia and hypokalaemia can be fatal
hypokalaemia deficient potassium in the blood
renin angiotensin system (RAS) hormone system that regulates blood pressure and fluid
balance
angiotensinogen a plasma protein produced by the liver
renin enzyme that catalyses angiotensinogen into angiotensin I and is produced by granular
cells in the juxtaglomerular apparatus of the nephron
angiotensin converting enzyme (ACE) enzyme that converts angiotensin I to angiotensin II
angiotensin II 8 amino acid peptide with a short half life and is a potent vasoconstrictor
principal cells receptors for ADH and aldosterone, acts in kidney at distal nephron
RAS pathway 1. angiotensinogen is converted into angiotensin I by renin
2.. angiotensin I is converted to angiotensin II by angiotensin converting enzyme
3. angiotensin II stimulates release of aldosterone from the adrenal cortex
