IB SEHS Topic 2

Which are involved in the regulation of heart rate? (multiple answers)

• SA Node

• Autonomic nervous system

• Adrenaline

• veins

Tags

NGSS.HS-LS1-3

Where in the heart is the electrical impulse generated for contraction?

• AV node

• Left atrium

• SA node

• Right ventricle

Which of the following correctly describes the sequence of excitation of heart muscle?

• AV node → bundle of HIS → SA node

• SA node → AV node → bundle of HIS

• bundle of HIS → SA node → AV node

• AV node → SA node → bundle of HIS

Which of the following best explains the cardiovascular drift?

• During prolonged exercise there is a lower venous return to the heart and a small decrease in blood volume due to sweating. Therefore the heart rate increases to maintain cardiac output

• During prolonged exercise there is a higher venous return to the heart and a increase in blood volume. Therefore the heart rate increases to maintain cardiac output

• During prolonged exercise there is a lower venous return to the heart and a decrease in blood volume due to sweating. Therefore the heart rate decreases to maintain cardiac output

Tags

NGSS.HS-LS1-3

What is cardiac output

• Stroke volume x heart rate

• the amount of blood that is pumped out of the heart each beat

• stroke volume x tidal volume

• the amount of blood that the heart can hold

An athlete’s resting heart rate is 60 bpm and stroke volume is 70 ml. What is the cardiac output of the athlete?

• 1300 ml min^–1

• 4200 ml min^–1

• 130 ml min^–1

• 420 ml min^–1

Where does blood exert the force measured as systolic blood pressure?

• On the arterial walls during ventricular relaxation

• On the venous walls during ventricular contraction

• On the arterial walls during ventricular contraction

• On the venous walls during ventricular relaxation

What is transported in the pulmonary artery?

• Oxygenated blood to working muscles

• Deoxygenated blood to working muscles

• Deoxygenated blood to the lungs

• Oxygenated blood to the lungs

How does the heart meet the demand for oxygenated blood during physical activity?

• Increasing cardiac output, decreasing stroke volume, increasing heart rate

• Decreasing cardiac output, decreasing stroke volume, decreasing heart rate

• Increasing cardiac output, increasing stroke volume, increasing heart rate

• Decreasing cardiac output, increasing stroke volume, increasing heart rate

Tags

NGSS.HS-LS1-3

What happens to someones blood pressure during dynamic exercise

• Systolic blood pressure increases and diastolic blood pressure remains constant

• Systolic blood pressure decreases and diastolic blood pressure increases

• both systolic and diastolic blood pressure increase proportionally with exercise intensity

• blood pressure remains unchanged

Tags

NGSS.HS-LS1-3