Modalities Practice Questions + Rationales |
PMHNP Liberty University
What is passive transport? - ANSWER -o Osmosis:
§ Passive movement of water or any solvent across the cellular membrane from an area of low
solute concentration to high solute concentration
§ Water is an important solvent, ie fluid that can dissolve the vital solutes we need to live
· Sodium, Potassium, Calcium, Chloride etc.
§ Our cellular membrane is very permeable to water as the solvent but not as permeable to the
solutes
§ Water will move as needed to achieve equivalent concentrations of solutes on both sides of the
membrane via osmosis
§ Balance of water must be maintained, or the cell will lyse due to high intracellular water
concentration
What is autosomal dominant disorder? - ANSWER -§ Passed from an affected parent to an
offspring, male and female are equally capable of transmission
§ One parent must have the trait
§ Can occur with homozygous and heterozygous allele pairs
§ Homozygous fetus is unlikely to survive or to have severe disability (disease will be doubly
severe with two expressing alleles)????
What is autosomal recessive disorder? - ANSWER -§ Single-gene mutations passed from an
affected parent to an offspring regardless of sex, but they occur only in homozygous (aa) allele
pairs
§ Heterozygous parents are carriers of the disorder but do not have the phenotype
§ Likely to continue through generations because of carriers
DEFINE VIRCHOW'S TRIAD. HOW IS THIS APPLICABLE TO THE DEVELOPMENT OF
CHRONIC CARDIOVASCULAR DISEASE? - ANSWER -Three conditions: endothelia injury,
sluggish blood flow, and increased coagulopathy> Virchow Triad > promote thrombus formation
§ When a vessel wall is injured, the endothelial damage attacks platelets and inflammatory
mediators to the site, thereby stimulating clot formation. Stagnant blood flow allows platelets
and clothing factors to accumulate and adhere to the vessel wall. Hypercoagulopathy states
promote clot formation inappropriately.
,o Most emboli in the arterial system originate in the left side of the heart and travel to other
organs such as the brain and the heart, causing an infarction.
What is HFrEF? - ANSWER -HFrEF (heart failure with reduced EF)àsystolic dysfunction
What is HFpEF? - ANSWER -HFpEF (heart failure with preserved EF)àdiastolic dysfunction
Can HFrEF and HFpEF occur together? - ANSWER -Yes, EF < or = to 40%
WHAT ARE THE LAYERS OF CARDIAC TISSUE - ANSWER -Epicardium, myocardium,
endocardium
Function of epicardium - ANSWER -Outer layer> protecting the heart, producing factors that
help the cardiac cells properly develop, and ensuring proper response to cardiac cell injury.
Function of myocardium - ANSWER -Muscle portion of the organ, thicker on left chambers...
why? à contracts and releases involuntarily and is responsible for keeping the heart pumping
blood around the body
§ Muscle of the heart
§ Muscles of the ventricles (especially Left Ventricle) are thicker than the atrium because the
distance and pressure against these chambers must pump blood
§ Atria are receiving chambers that pump blood to their respective ventricles
§ Ventricles pump blood to the low-pressure lungs and high-pressure circulation
function of the endocardium - ANSWER -Inner epithelial layer making up cardiac valves -->
keeps the blood flowing through the heart separate from the myocardium, or cardiac muscles
§ Valves function to ensure one-way flow of blood through the heart
DESCRIBE THE PROCESS OF NORMAL BLOOD FLOW THROUGH THE
CARDIOVASCULAR SYSTEM. - ANSWER -o Blood low in oxygen enters the right atrium
from systemic circulation through superior/inferior vena cavas
o Blood flows from right atrium to right ventricle during ventricular diastole through the
tricuspid valve--At end ventricular diastole, atria contracts to push last of blood into right
ventricle (atrial kick)
o Rising ventricular pressure causes tricuspid valve to close--pressure becomes higher in right
ventricle than pulmonary artery, pulmonic valve opens and blood moves forward
o Blood is carried to lungs via pulmonary arteries for oxygenation
o Pressure in the right ventricle drops, closing the pulmonic valve.
o After oxygenation in the lungs, blood is carried to the left side of the heart via the pulmonary
veins and enters the left atrium
,o Left atrium blood flows into left ventricle through the mitral valve during ventricular diastole--
Atrial kick
o As left ventricular pressure increases, mitral valve closes
o When ventricular pressure exceeds aortic pressure, aortic valve opens, ventricle contracts and
ejects blood through aorta
o Blood is transported via the systemic circulation to the body
WHAT CAUSES THE NORMAL HEART SOUNDS OF S1/S2? - ANSWER -The S1 heart
sound is the closing of the atrioventricular (tricuspid and mitral) valves
The S2 heart sound is the closing of the semilunar (aortic [A1] and pulmonic [P2]) valves
WHEN IN THE CARDIAC CYCLE DO CORONARY ARTERIES PERFUSE? - ANSWER -
Diastole; Coronary vasculature is compressed by contracting myocardium
DESCRIBE THE PROCESS OF NORMAL CARDIAC CONDUCTION - ANSWER -SA
node>AV Node>Bundle of His>Purkinje Fibers
P wave is? - ANSWER -atrial depolarization
QRS complex is - ANSWER -ventricular depolarization
T wave is - ANSWER -ventricular repolarization
What is automaticity? - ANSWER -All cardiac myocytes can contract independently and
generate electrical impulses without external stimulus
What is excitability? - ANSWER -Ability of the cells to respond to electrical impulses (refers to
the myocyte's ability to respond to the electrical impulse generated by a neighboring cell)
What are the major ions - ANSWER -Calcium, sodium and potassium
what is the major intracellular cation? - ANSWER -potassium
what is the major extracellular ion? - ANSWER -sodium
Describe the new action potential in producing cardiac action potential within a myocyte -
ANSWER -§ Potassium leaves the cell via potassium cells, leaving behind a very negative
membrane potential
§ Sodium and calcium start leaking through gap junctions, membrane becomes more positive
, § Fast (voltage-gated) sodium channels open and sodium floods the cell, driving the membrane
potential way up
§ Fast sodium channels close, depolarization occurs
§ Voltage-gated potassium channels open because depolarization happened
§ Potassium starts leaking outwards again, membrane potential goes down
§ Calcium voltage-gated channels open and calcium moves into the cell
§ Because potassium is moving out and calcium is moving in, flatline occurs in membrane
potential
o Calcium channels close, potassium channels eventually close, potassium returns to slowly
leaking out of cells and membrane potential repolarizes
what is blood pressure? - ANSWER -o Cardiac Output x Systemic Vascular Resistance
what is pulse pressure? - ANSWER -Difference between systolic and diastolic pressures; force
the heart generates with contraction
What is cardiac output? - ANSWER -o The amount of blood the heart pumps in one minute
§ Cardiac Output = Stroke Volume x Heart Rate (4-8L/min)
What is stroke volume? - ANSWER -The amount of blood (ml) ejected from the heart with each
beat
§ Example: Cardiac Output= Stroke Volume (75ml x 80 BPM = 6L/min)
§ Affected by preload, afterload and contractility
What is ejection fraction? - ANSWER -Amount of blood pumped out with each contraction
relative to blood volume at the end of diastole (%)
What is systemic vascular resistance? - ANSWER -Resistance within the circulatory system
PULMONARY ANATOMY. WHICH STRUCTURES ARE RESPONSIBLE FOR AIR
CONDUCTION - ANSWER -Air-conduction portion (delivers to lung) --
· Structures include the nasal cavity, oral cavity, sinuses, pharynx, epiglottis, larynx, trachea and
mainstem bronchi, bronchioles
PULMONARY ANATOMY. WHICH STRUCTURES ARE RESPONSIBLE FOR GAS
EXCHANGE - ANSWER -Alveoli: provides area for exchange of oxygen and CO2
DESCRIBE THE NORMAL RESPIRATORY BREATH CYCLE.
WHAT IS PASSIVE, WHAT IS ACTIVE? - ANSWER -Inspiration is an active neural process
and expiration is passive—does not require muscle contraction.