BIO 207 Rourke Exam 3 Questions and Answers Already Passed Rated A+
Cardiac Muscle - Answers Involuntary muscle tissue found only in the heart. HAs intercalated discs to
help function as only one unit, pacemaker cells are self-excitatory, gap junctions present
Pericardial Sac - Answers Two layers with serous pericardial fluid in between, The inner layer is the
serous layer and the outer fibrous layer protect the heart.
Heart Sounds - Answers First Heart Sound: LUB, caused by the closing of the AV Valves
Second Heart Sound: DUB caused by the closing of the Semilunar Valves
Atrioventricular Valves - Answers Separate the atria from the ventricles, include the tricuspid and the
mitral (bicuspid) valves.
Semilunar Valves - Answers The aortic valve and the pulmonary valve
Problems with valves - Answers Stenotic: valve does not open correctly, creates a turbulent flow,
resulting in a murmur, narrow valve causes turbulence during ejection.
Leaky: valve does not close correctly, creating a turbulent backflow that can be heard after ventricular
contraction.
Structure of valves - Answers Open/Close in response to pressure behind or in front of respectively.
Chordae Tendineae attach to papillary muscle to prevent the valve from inverting from ventricular back
pressure
Heart Layer - Answers Endocardium (deep): inner layer of heart, covers entire inner surface of heart
including valves.
Myocardium (middle layer): thickest because it is muscle
Epicardium (outermost layer): what I would grab if I were to hold to heart in my hands
Myocardial/ Contractile Cells - Answers Produce Contraction that propel blood
continuous involuntary rhythmic contraction
Conducting Cells - Answers Connect SA and AV nodes
allow the AP to go through the Myocardium
Pacemaker Cells - Answers Involved in gap junctions
self excitatory, establish rate of contraction
highest rate of depolarization
, Pulmonary Circulation - Answers Blood flowing out right ventricle to lungs through pulmonary arteries to
undergo gas exchange and get oxygenated and flow back to heart
Systemic Circulation - Answers U already know this bitch
Pulmonary and Systemic Circulation - Answers there is the same amount of blood flowing throughout
each system at any given time. If the Sympathetic nervous system is working there would be less blood
going to GI Tract and more to skeletal muscle. The lungs cannot have high pressure or else the blood
would not have enough time to oxygenate
ectopic - Answers purkinje fibers are going way to fast and the whole heart now lets purkinje fibers drive
up heart rate
Ventricular Action Potential - Answers 4 phases: 1. Rapid Depolarization: Na fast channels open, Na+
rush in
2. Partial Repolarization: inactivation of Na+, Opening of voltage gated Ca2+, K+ out
3. Plateau: Voltage gated Ca2+ in slowly to prevent tetanus
4. Repolarization: closure of Ca 2+ channels, opening of Voltage gated K+ channels,
Resting Membrane Potential: -90mV
Threshold: -70mV
Peak @ +30mV
Parasympathetic affects on the Heart - Answers drives heart rate down, only affects SA Node, ACh
muscarinic receptors of auto rhythmic cells K+ goes out and Ca2+ going in, hyper polarizing the cell and
slowing the rate of depolarization, lowering heart rate.
Sympathetic affects on heart - Answers Norepinephrine binds to Beta 1 receptors auto rhythmic cells
Na+ and Ca2+ influx= faster depolarization= increase in heart rate
Systole - Answers Contraction, Depolarization, P wave, QRS Complex,
Diastole - Answers Relaxation, Repolarization of T wave
P wave - Answers atrial depolarization (contraction)
PR Segment - Answers AV Node Delay, Ventricular Filling completely
QRS Complex - Answers ventricular depolarization (contraction)
ST segment - Answers time during which ventricles are contracting and emptying
T wave - Answers Ventricular Repolarization, relaxation
Cardiac Muscle - Answers Involuntary muscle tissue found only in the heart. HAs intercalated discs to
help function as only one unit, pacemaker cells are self-excitatory, gap junctions present
Pericardial Sac - Answers Two layers with serous pericardial fluid in between, The inner layer is the
serous layer and the outer fibrous layer protect the heart.
Heart Sounds - Answers First Heart Sound: LUB, caused by the closing of the AV Valves
Second Heart Sound: DUB caused by the closing of the Semilunar Valves
Atrioventricular Valves - Answers Separate the atria from the ventricles, include the tricuspid and the
mitral (bicuspid) valves.
Semilunar Valves - Answers The aortic valve and the pulmonary valve
Problems with valves - Answers Stenotic: valve does not open correctly, creates a turbulent flow,
resulting in a murmur, narrow valve causes turbulence during ejection.
Leaky: valve does not close correctly, creating a turbulent backflow that can be heard after ventricular
contraction.
Structure of valves - Answers Open/Close in response to pressure behind or in front of respectively.
Chordae Tendineae attach to papillary muscle to prevent the valve from inverting from ventricular back
pressure
Heart Layer - Answers Endocardium (deep): inner layer of heart, covers entire inner surface of heart
including valves.
Myocardium (middle layer): thickest because it is muscle
Epicardium (outermost layer): what I would grab if I were to hold to heart in my hands
Myocardial/ Contractile Cells - Answers Produce Contraction that propel blood
continuous involuntary rhythmic contraction
Conducting Cells - Answers Connect SA and AV nodes
allow the AP to go through the Myocardium
Pacemaker Cells - Answers Involved in gap junctions
self excitatory, establish rate of contraction
highest rate of depolarization
, Pulmonary Circulation - Answers Blood flowing out right ventricle to lungs through pulmonary arteries to
undergo gas exchange and get oxygenated and flow back to heart
Systemic Circulation - Answers U already know this bitch
Pulmonary and Systemic Circulation - Answers there is the same amount of blood flowing throughout
each system at any given time. If the Sympathetic nervous system is working there would be less blood
going to GI Tract and more to skeletal muscle. The lungs cannot have high pressure or else the blood
would not have enough time to oxygenate
ectopic - Answers purkinje fibers are going way to fast and the whole heart now lets purkinje fibers drive
up heart rate
Ventricular Action Potential - Answers 4 phases: 1. Rapid Depolarization: Na fast channels open, Na+
rush in
2. Partial Repolarization: inactivation of Na+, Opening of voltage gated Ca2+, K+ out
3. Plateau: Voltage gated Ca2+ in slowly to prevent tetanus
4. Repolarization: closure of Ca 2+ channels, opening of Voltage gated K+ channels,
Resting Membrane Potential: -90mV
Threshold: -70mV
Peak @ +30mV
Parasympathetic affects on the Heart - Answers drives heart rate down, only affects SA Node, ACh
muscarinic receptors of auto rhythmic cells K+ goes out and Ca2+ going in, hyper polarizing the cell and
slowing the rate of depolarization, lowering heart rate.
Sympathetic affects on heart - Answers Norepinephrine binds to Beta 1 receptors auto rhythmic cells
Na+ and Ca2+ influx= faster depolarization= increase in heart rate
Systole - Answers Contraction, Depolarization, P wave, QRS Complex,
Diastole - Answers Relaxation, Repolarization of T wave
P wave - Answers atrial depolarization (contraction)
PR Segment - Answers AV Node Delay, Ventricular Filling completely
QRS Complex - Answers ventricular depolarization (contraction)
ST segment - Answers time during which ventricles are contracting and emptying
T wave - Answers Ventricular Repolarization, relaxation
