GMS 6474 Mega Final questions well
answered to pass
I band - correct answer ✔✔- thin filaments
- titin
- z disc
A band - correct answer ✔✔- thick and thin filaments
H zone - correct answer ✔✔- thick filaments
M line - correct answer ✔✔- middle
- thick filaments
Sarcoplamic reticulum - correct answer ✔✔- membraneous smooth ER
- wraps around sarcomeres throughout myofibrils
- stores Ca2+
Triad - correct answer ✔✔- sarcoplasmic reticulum
- terminal cisterna
- t-tubules
- joining
Transmural pressure - correct answer ✔✔- Pi - Po
- pressure difference across a vessel wall
,Eeq - correct answer ✔✔- (-61.5/z) log(inside/outside)
- equilibrium potential
Ena - correct answer ✔✔- +60 mV
Ek - correct answer ✔✔- -90 mV
Eca - correct answer ✔✔- +130 mV
Fast voltage-gated Na+ channels - correct answer ✔✔- open at -70 mV
- similar to those in muscle and neural tissue
- rapid activation - opening of m gates
- rapid inactivation - closure of h gates
- Na enters down concentration gradient
- generates inward membrane potential
Cardiac K+ channels - correct answer ✔✔- outward flow
- inward rectifyer
- transient outward K+ current
- 2x delayed rectifyer K+ currents
Cardiac Ca2+ channels - correct answer ✔✔- T-type
- L-type (more prevalent)
T-type Ca2+ channels - correct answer ✔✔- tiny conductance
- transient openings
- mostly in pacemaker and atrial tissue
- opens at -55 mV
- fairly rapid inactivation
,L-type Ca2+ channels - correct answer ✔✔- large conductance
- long lasting opening
- all throughout heart
- open at -40 mV
- slower inactivation
- inward (depolarizing) current
Mixed conductance channels - correct answer ✔✔- funny current (If)
- permeable to Na+ & K+
- activated by hyperpolarization
- net inward Na+ current
- small conductance channel
60-100 - correct answer ✔✔- SA node normal pace
40-60 - correct answer ✔✔- AV node normal pace
20-40 - correct answer ✔✔- purkinje system
Postive deflection - correct answer ✔✔- leads 3, 4, 5, 6
Negative deflection - correct answer ✔✔- AVR
No deflection - correct answer ✔✔- Lead 1 & AVL
Frontal plane view - correct answer ✔✔- I, II, III aVR, aVL, aVF
Lead I - correct answer ✔✔- right arm (-)
, - left arm (+)
Lead II - correct answer ✔✔- right arm (-)
- left foot (+)
Lead III - correct answer ✔✔- left arm (-)
- left foot (+)
Precordial leads - correct answer ✔✔- V1-6
- record electrical activity in transverse plane (horizontally)
- wrapped around view
T-wave postive deflection - correct answer ✔✔- becasue repolarization impulse occurs in an opposite
direction to depolarization
- pericardial to endocardial
QRS duration - correct answer ✔✔- normal 0.04 - 0.12 secs
- 3 small boxes
Small box - correct answer ✔✔- 0.04 sec
Big box - correct answer ✔✔- 0.2 sec
PR interval - correct answer ✔✔- 0.12 - 0.20 sec
- 1 large box
QT interval - correct answer ✔✔- 1/2 RR
Mobitz Type I - correct answer ✔✔- longer, longer, longer, drop
answered to pass
I band - correct answer ✔✔- thin filaments
- titin
- z disc
A band - correct answer ✔✔- thick and thin filaments
H zone - correct answer ✔✔- thick filaments
M line - correct answer ✔✔- middle
- thick filaments
Sarcoplamic reticulum - correct answer ✔✔- membraneous smooth ER
- wraps around sarcomeres throughout myofibrils
- stores Ca2+
Triad - correct answer ✔✔- sarcoplasmic reticulum
- terminal cisterna
- t-tubules
- joining
Transmural pressure - correct answer ✔✔- Pi - Po
- pressure difference across a vessel wall
,Eeq - correct answer ✔✔- (-61.5/z) log(inside/outside)
- equilibrium potential
Ena - correct answer ✔✔- +60 mV
Ek - correct answer ✔✔- -90 mV
Eca - correct answer ✔✔- +130 mV
Fast voltage-gated Na+ channels - correct answer ✔✔- open at -70 mV
- similar to those in muscle and neural tissue
- rapid activation - opening of m gates
- rapid inactivation - closure of h gates
- Na enters down concentration gradient
- generates inward membrane potential
Cardiac K+ channels - correct answer ✔✔- outward flow
- inward rectifyer
- transient outward K+ current
- 2x delayed rectifyer K+ currents
Cardiac Ca2+ channels - correct answer ✔✔- T-type
- L-type (more prevalent)
T-type Ca2+ channels - correct answer ✔✔- tiny conductance
- transient openings
- mostly in pacemaker and atrial tissue
- opens at -55 mV
- fairly rapid inactivation
,L-type Ca2+ channels - correct answer ✔✔- large conductance
- long lasting opening
- all throughout heart
- open at -40 mV
- slower inactivation
- inward (depolarizing) current
Mixed conductance channels - correct answer ✔✔- funny current (If)
- permeable to Na+ & K+
- activated by hyperpolarization
- net inward Na+ current
- small conductance channel
60-100 - correct answer ✔✔- SA node normal pace
40-60 - correct answer ✔✔- AV node normal pace
20-40 - correct answer ✔✔- purkinje system
Postive deflection - correct answer ✔✔- leads 3, 4, 5, 6
Negative deflection - correct answer ✔✔- AVR
No deflection - correct answer ✔✔- Lead 1 & AVL
Frontal plane view - correct answer ✔✔- I, II, III aVR, aVL, aVF
Lead I - correct answer ✔✔- right arm (-)
, - left arm (+)
Lead II - correct answer ✔✔- right arm (-)
- left foot (+)
Lead III - correct answer ✔✔- left arm (-)
- left foot (+)
Precordial leads - correct answer ✔✔- V1-6
- record electrical activity in transverse plane (horizontally)
- wrapped around view
T-wave postive deflection - correct answer ✔✔- becasue repolarization impulse occurs in an opposite
direction to depolarization
- pericardial to endocardial
QRS duration - correct answer ✔✔- normal 0.04 - 0.12 secs
- 3 small boxes
Small box - correct answer ✔✔- 0.04 sec
Big box - correct answer ✔✔- 0.2 sec
PR interval - correct answer ✔✔- 0.12 - 0.20 sec
- 1 large box
QT interval - correct answer ✔✔- 1/2 RR
Mobitz Type I - correct answer ✔✔- longer, longer, longer, drop
