344 Test 2 Study Guide Topics Flashcards
Increase in ADH ___ urine output
decreases
Decrease in ADH increases __ output
urine
Normal Sodium levels
135 to 145 mEq/L
Sodium attracts
water
Special cells in the kidneys monitor for __ levels
sodium
If the kidneys detect a decrease in sodium levels, __ is released which (indirectly) causes blood pressure to rise
renin
When you have too much sodium (hypernatremia) your kidneys cannot excrete the excess sodium and also retain water at the same time. This increased fluid volume raises
blood pressure
Sodium is also used to determine the concentration of
urine
Potassium is mostly ___ the cell membrane during rest
inside
when the cell is stimulated, potassium
flows out
An increase in K+ (hyperkalemia) causes the resting membrane potential to become more
positive
An increase in K+ (hyperkalemia) causes the resting membrane potential to become more positive moving it closer to the
threshold
plays key roles in cell signaling
calcium
plays key roles in muscle contraction
calcium
plays key roles in blood clotting
calcium
Normal calcium level is
8.5 to 10.5 mg/dL
Calcium affects __ ___ and automaticity via calcium channels
cardiac contractility
a special process in cardiac muscle where calcium ions diffuse in, making the cell more positive (depolarizing toward threshold)
Calcium leak
As part of the normal contraction cycle, heart cells have a special phase called
plateau
Cardiac cell remains above __ potential during plateau (remains active).
threshold
The plateau phase happens because ___ ___ continue allowing calcium ions to leak in, keeping the membrane positive.
calcium channels
The heart cell contraction ends when the calcium channels ___; this ends the plateau and the cell repolarizes
close
Calcium channel blockers are used as ___ drugs
antihypertensive
drugs that relax and widen blood vessels by affecting the muscle cells in the arterial walls.
Calcium channel blockers