HES WEEK 5 - HEART
ANATOMY AND
ELECTROPHYSIOLOGY WITH
CORRECT QUESTION AND
ANSWERS 2025/2026
→ cycle is divided into four main phases: defined by actions of ventricles and positions of
valves: - correct answersfilling, contraction, ejection, and relaxation
3. Repolarization phase: - correct answersCa2+ channels close and voltage-gated K+ channels
open, causing K+ outflow and membrane repolarization
→ K+ flows out via K+ channels causing the repolarization phase of the Action Potential in
pacemaker cells
Ca closes
K flows out
- causing repolarization
4. Minimum potential phase - correct answersK+ channels remain open, and the membrane
hyperpolarizes. This opens HCN channels, and the cycle repeats
→ HCN channels open again in response to the hyperpolarization from K+ flowing out
,K+ out still and cycle eventually repeats
anatomy of the atrioventricular and semilunar valves - correct answers
as ventricles contract and relax, - correct answerspressure in chambers changes, causing blood
to push on valves and open or close them
AV valves - correct answerstricuspid and bicuspid
big picture of blood flow through the heart - correct answersBlood in systemic capillaries
delivers oxygen to body cells
Systemic veins return deoxygenated blood to the right atrium
Blood passes from the right atrium through the tricuspid valve to the right ventricle
The right ventricle pumps blood through the pulmonary valve to the pulmonary trunk
The pulmonary trunk delivers blood to the pulmonary capillaries of the left and right lungs
The blood becomes oxygenated in the pulmonary capillaries and the pulmonary veins return
oxygenated blood to the left atrium
Blood passes from the left atrium through the mitral valve to the left ventricles
The left ventricle pumps blood through the aortic valve to the aorta
, The aorta delivers blood to the systemic capillaries and the cycle continues
Blood flows in response to what? - correct answerspressure gradients
Cardiac Cycle - Step 2: Isovolumetric Contraction Phase - correct answersIsovolumetric because
the pressure in the ventricles is not yet high enough to push open the semilunar valves
- Ventricular systole begins.
- AV and semilunar (aortic and pulmonary) valves close when enough pressure builds in the
ventricles
- Atrial diastole begins
Cardiac Cycle - Step 3: Ventricular Ejection Phase - correct answersAt rest, approximately 70 ml
of blood is pumped from each ventricle
- Ventricular systole continues
- AV valves are still closed
- Atrial diastole continues
- Pressure opens SL valves, and blood is ejected into the pulmonary artery and aorta
Cardiac Cycle - Step 4: Isovolumetric Relaxation - correct answersIsovolumetric because blood is
neither being ejected from nor entering into the ventricles. Volume briefly remains constant in
the ventricles
The pressure in the ventricles is still somewhat higher than in the atria, so AV valves remain
closed at this point
- Ventricular diastole begins
ANATOMY AND
ELECTROPHYSIOLOGY WITH
CORRECT QUESTION AND
ANSWERS 2025/2026
→ cycle is divided into four main phases: defined by actions of ventricles and positions of
valves: - correct answersfilling, contraction, ejection, and relaxation
3. Repolarization phase: - correct answersCa2+ channels close and voltage-gated K+ channels
open, causing K+ outflow and membrane repolarization
→ K+ flows out via K+ channels causing the repolarization phase of the Action Potential in
pacemaker cells
Ca closes
K flows out
- causing repolarization
4. Minimum potential phase - correct answersK+ channels remain open, and the membrane
hyperpolarizes. This opens HCN channels, and the cycle repeats
→ HCN channels open again in response to the hyperpolarization from K+ flowing out
,K+ out still and cycle eventually repeats
anatomy of the atrioventricular and semilunar valves - correct answers
as ventricles contract and relax, - correct answerspressure in chambers changes, causing blood
to push on valves and open or close them
AV valves - correct answerstricuspid and bicuspid
big picture of blood flow through the heart - correct answersBlood in systemic capillaries
delivers oxygen to body cells
Systemic veins return deoxygenated blood to the right atrium
Blood passes from the right atrium through the tricuspid valve to the right ventricle
The right ventricle pumps blood through the pulmonary valve to the pulmonary trunk
The pulmonary trunk delivers blood to the pulmonary capillaries of the left and right lungs
The blood becomes oxygenated in the pulmonary capillaries and the pulmonary veins return
oxygenated blood to the left atrium
Blood passes from the left atrium through the mitral valve to the left ventricles
The left ventricle pumps blood through the aortic valve to the aorta
, The aorta delivers blood to the systemic capillaries and the cycle continues
Blood flows in response to what? - correct answerspressure gradients
Cardiac Cycle - Step 2: Isovolumetric Contraction Phase - correct answersIsovolumetric because
the pressure in the ventricles is not yet high enough to push open the semilunar valves
- Ventricular systole begins.
- AV and semilunar (aortic and pulmonary) valves close when enough pressure builds in the
ventricles
- Atrial diastole begins
Cardiac Cycle - Step 3: Ventricular Ejection Phase - correct answersAt rest, approximately 70 ml
of blood is pumped from each ventricle
- Ventricular systole continues
- AV valves are still closed
- Atrial diastole continues
- Pressure opens SL valves, and blood is ejected into the pulmonary artery and aorta
Cardiac Cycle - Step 4: Isovolumetric Relaxation - correct answersIsovolumetric because blood is
neither being ejected from nor entering into the ventricles. Volume briefly remains constant in
the ventricles
The pressure in the ventricles is still somewhat higher than in the atria, so AV valves remain
closed at this point
- Ventricular diastole begins
