DETAILED ANSWERS|LATEST UPDATE!!!!!!2026|GUARANTEED
CORRECT = 100
100
INCORRECT=0
STUDY MATERIALS.......DESIGNED TO HELP YOU SUCCEED
SPOTLIGHT 1
1
, WELL DETAILED ANSWERS|LATEST
UPDATE!!!!!!2026|GUARANTEED PASS|GRADED
Cardia structure/blood flow - ANSWER The right atrium receives deoxygenated
blood from the body. The blood travels from the right atrium, through the tricuspid valve to
the right ventricle. From the right ventricle the blood travels through the pulmonic valve,
into the pulmonary artery (this is the only artery in the body which carries deoxygenated
blood), into the lungs, where it goes to the alveoli and gas exchange occurs. The oxygenated
blood then enters the pulmonary vein and is delivered to the left atrium. From the left
atrium it travels through the mitral valve into the left ventricle. From the left ventricle the
blood travels through the aortic valve into the aorta
Fetal circulation - ANSWER The umbilical vein receives oxygenated blood from the
placenta. The umbilical vein connects to the hepatic circulation but also connects to the
inferior vena cava by the ductus venosus. The ductus venosus allows the oxygen-rich blood
to enter the inferior vena cava and some blood does enter the hepatic circulation. From the
inferior vena cava, the blood is emptied into the right atrium. The most oxygenated blood in
the right atrium is shunted through the foramen ovale (this is an opening between the right
and left atria) into the left atrium. The blood then enters the left ventricle and is pumped out
to the head and the rest of the body. The deoxygenated blood also enters the right atrium
just as the oxygenated blood does. There are two streams that help to keep the blood
separate. Sixty percent of the blood in the right atrium (which is oxygenated blood) will be
moved forward as described above. The remaining 40% of the blood is mixed blood
(oxygenated and deoxygenated) and will move from the right atrium, to the right ventricle,
and into the pulmonary artery. From the pulmonary artery it will pass through the patent
ductus arteriosus (which is a connection between the pulmonary artery and the aorta) into
the aorta. The aorta will connect with the umbilical artery, where the blood will go back to
the placenta to exchange gas, get rid of waste products and pick up nutrients. The right side
of the heart has the higher pressure prior to birth. After birth, this changes with the
neonate's first breath and the left side of the heart becomes the one with the higher
pressure.
2
, Factors which increase contraction - ANSWER **Catecholamines-increase activity of
the calcium pump in the sarcoplasmic reticulum; therefore it increases the release of
calcium from the SR**Increases in intracellular calcium**Decreased extracellular sodium-
decreases the activity of the Na/Ca exchanger**Digitalis-blocks the Na/K pump which
increases intracellular Na, decreases the activity of the NA/Ca exchanger, and increases
intracellular Ca
Factors which decrease contraction - ANSWER **Beta blockers-block the effects of
the catecholamines**heart failure with systolic
dysfunction**acidosis**hypoxia/hypercapnia **nondihydropyridine calcium channel
blockers
Cardiac output (CO) - ANSWER Amount of blood pushed from the left ventricle in 1
minutes. HR X STROKE VOLUME = CO. Normal output is 5L/minute
Stroke Volume - ANSWER Amount of blood ejected by the ventricle for each cardiac
cycle. Highly dependent on the force of contraction. Contraction is dependent upon amount
of preload, stimulation by endogenous positive inotropic agents such as epi and norepi,
presence of negative inotropic agents and adequacy of myocardial oxygenation
Ejection fraction (EF) - ANSWER Percentage of blood which is ejected from the
ventricle with each contraction. Calculated by dividing the stroke volume by the end diastolic
volume. Normal EF is 55-65%. EF decreases with systolic heart failure but not in diastolic
heart failure
Preload - ANSWER Made up of end diastolic volume and end diastolic pressure.
Dependent upon the amount of venous return to the heart and the amount of blood left in
the left ventricle at the end of systole. Increased preload can cause heart failure from a
decline in stroke volume and a back up into pulmonary circulation
Afterload - ANSWER Resistance that the ventricle pushes against to contract. This
includes aortic pressure and systemic vascular resistance. High afterload increases the work
3
CORRECT = 100
100
INCORRECT=0
STUDY MATERIALS.......DESIGNED TO HELP YOU SUCCEED
SPOTLIGHT 1
1
, WELL DETAILED ANSWERS|LATEST
UPDATE!!!!!!2026|GUARANTEED PASS|GRADED
Cardia structure/blood flow - ANSWER The right atrium receives deoxygenated
blood from the body. The blood travels from the right atrium, through the tricuspid valve to
the right ventricle. From the right ventricle the blood travels through the pulmonic valve,
into the pulmonary artery (this is the only artery in the body which carries deoxygenated
blood), into the lungs, where it goes to the alveoli and gas exchange occurs. The oxygenated
blood then enters the pulmonary vein and is delivered to the left atrium. From the left
atrium it travels through the mitral valve into the left ventricle. From the left ventricle the
blood travels through the aortic valve into the aorta
Fetal circulation - ANSWER The umbilical vein receives oxygenated blood from the
placenta. The umbilical vein connects to the hepatic circulation but also connects to the
inferior vena cava by the ductus venosus. The ductus venosus allows the oxygen-rich blood
to enter the inferior vena cava and some blood does enter the hepatic circulation. From the
inferior vena cava, the blood is emptied into the right atrium. The most oxygenated blood in
the right atrium is shunted through the foramen ovale (this is an opening between the right
and left atria) into the left atrium. The blood then enters the left ventricle and is pumped out
to the head and the rest of the body. The deoxygenated blood also enters the right atrium
just as the oxygenated blood does. There are two streams that help to keep the blood
separate. Sixty percent of the blood in the right atrium (which is oxygenated blood) will be
moved forward as described above. The remaining 40% of the blood is mixed blood
(oxygenated and deoxygenated) and will move from the right atrium, to the right ventricle,
and into the pulmonary artery. From the pulmonary artery it will pass through the patent
ductus arteriosus (which is a connection between the pulmonary artery and the aorta) into
the aorta. The aorta will connect with the umbilical artery, where the blood will go back to
the placenta to exchange gas, get rid of waste products and pick up nutrients. The right side
of the heart has the higher pressure prior to birth. After birth, this changes with the
neonate's first breath and the left side of the heart becomes the one with the higher
pressure.
2
, Factors which increase contraction - ANSWER **Catecholamines-increase activity of
the calcium pump in the sarcoplasmic reticulum; therefore it increases the release of
calcium from the SR**Increases in intracellular calcium**Decreased extracellular sodium-
decreases the activity of the Na/Ca exchanger**Digitalis-blocks the Na/K pump which
increases intracellular Na, decreases the activity of the NA/Ca exchanger, and increases
intracellular Ca
Factors which decrease contraction - ANSWER **Beta blockers-block the effects of
the catecholamines**heart failure with systolic
dysfunction**acidosis**hypoxia/hypercapnia **nondihydropyridine calcium channel
blockers
Cardiac output (CO) - ANSWER Amount of blood pushed from the left ventricle in 1
minutes. HR X STROKE VOLUME = CO. Normal output is 5L/minute
Stroke Volume - ANSWER Amount of blood ejected by the ventricle for each cardiac
cycle. Highly dependent on the force of contraction. Contraction is dependent upon amount
of preload, stimulation by endogenous positive inotropic agents such as epi and norepi,
presence of negative inotropic agents and adequacy of myocardial oxygenation
Ejection fraction (EF) - ANSWER Percentage of blood which is ejected from the
ventricle with each contraction. Calculated by dividing the stroke volume by the end diastolic
volume. Normal EF is 55-65%. EF decreases with systolic heart failure but not in diastolic
heart failure
Preload - ANSWER Made up of end diastolic volume and end diastolic pressure.
Dependent upon the amount of venous return to the heart and the amount of blood left in
the left ventricle at the end of systole. Increased preload can cause heart failure from a
decline in stroke volume and a back up into pulmonary circulation
Afterload - ANSWER Resistance that the ventricle pushes against to contract. This
includes aortic pressure and systemic vascular resistance. High afterload increases the work
3
