Heart Rate & CVS

Question 1

Starling’s law of the heart

Answer 1

With increasing venous return stroke volume increases

Question 2

MAP equation

Answer 2

MAP= diastolic + ( systolic - diastolic / 3)

Question 3

Factors affecting blood pressure

Answer 3

• Age
• gender
• posture
• exercise
• hydrostatic pressure

Question 4

MAP

Answer 4

MAP=CO x TPR

Question 5

Purposes of the CVS

Answer 5

• Transport of substances
• removal of metabolic waste
• distribution of hormones
• homeostasis eg. Temp regulation

Question 6

Systemic circulation

Answer 6

Supplies blood to body

Question 7

Pulmonary circulation

Answer 7

Blood to lungs

Question 8

Darcy’s law

Answer 8

Flow = pressure difference / resistance

Question 9

Why is there a delay at the AVN?

Answer 9

To allow the atria to empty before ventricular contraction begins

Question 10

Poiseuille’s law

Answer 10

Resistance= length X viscosity /3.14 x r4

Question 11

Darcy + poiseuille ‘s law

Answer 11

Flow = pressure difference x r4

Question 12

During light to moderate exercise systolic and diastolic pressure ________, but during moderate to vigorous exercise systolic pressure ________ and diastolic pressure ________ .

Answer 12

During mild to moderate exercise, the increase in cardiac output is greater than overall vasodilation. Therefore, both systolic and diastolic blood pressure tend to increase. In moderate to severe exercise, vasodilation in the exercising muscle and the skin results in an increase in systolic pressure accompanied by a decrease in diastolic pressure.