Lecture 10

Question 1

What is the format blood pressure is usually shown in?

Answer 1

Systolic BP over Diastolic BP

Question 2

What is the highest pressure detected in the arteries?

Answer 2

Systolic, when the heart is contracting

Question 3

What is the lowest pressure in the arteries?

Answer 3

Diastolic, when the heart is relaxing

Question 4

Blood pressure falls steeply across what?

Answer 4

Arterioles, capillaries and venues

Question 5

Where is blood pressure most oscillatory in nature?

Answer 5

In major arteries where blood pressure is high

Question 6

Where is blood pressure the lowest?

Answer 6

In veins, furtherest away from the left ventricle

Question 7

What creates a driving force for blood flow?

Answer 7

Large difference in pressure between arterial and venous sides. creates a concentration gradient

Question 8

What does blood flow in cause?

Answer 8

Fills arteries
increases arterial blood volume
raises arterial pressure

Question 9

Blood flow out causes?

Answer 9

Arteries to be drained
decrease in arterial blood volume
lowers arterial pressure

Question 10

What is cardiac output?

Answer 10

ventricular contraction causing an ejection of blood

Question 11

Blood flow out is controlled by?

Answer 11

resistance of the arteries into capillary beds

Question 12

How to increase cardiac output?

Answer 12

Increase in flow

Question 13

How to increase resistance?

Answer 13

decrease outflow

Question 14

Mean arterial pressure =

Answer 14

CO x TPR

Question 15

Cardiac output =

Answer 15

SV x HR

Question 16

what is stroke volume?

Answer 16

Litres per beat

Question 17

what is heart rate?

Answer 17

Beats pre minute

Question 18

Which phase of the cardiac cycle does the volume of blood rapidly decrease?

Answer 18

ventricular ejection

Question 19

If the stroke volume is high will the heart rate be high low?

Answer 19

Low because CO = SV x HR

Question 20

What are baroreceptors?

Answer 20

blood pressure sensors

Question 21

two examples of where baroreceptors are?

Answer 21

Carotid artery

aorta

Question 22

Why is the left side of the heart required to function at high pressure?

Answer 22

because it supplies blood to the entire body

Question 23

What is contraction strength?

Answer 23

Stroke volume

Question 24

What is contraction speed?

Answer 24

Heart rate

Question 25

When does the first sound wave happen? (ECG)

Answer 25

After the QRS wave

Question 26

Where does the second sound wave happen? (ECG)

Answer 26

After the T wave

Question 27

What nervous system does the Vagus nerve innervate?

Answer 27

Parasympathetic

Question 28

Where does the Vagus nerve sit in the spinal cord?

Answer 28

Dorsal motor nucleus of vagus. Cardioinhibitory centre

Medulla oblongata

Question 29

What does the vagus nerve do?

Answer 29

Decreases heart rate

Question 30

What does the vagus nerve act on?

Answer 30

the SA node and AV node

Question 31

Describe the pathway of the sympathetic cardiac nerves?

Answer 31

Begins in the cardioacceleratory centre in medulla oblongata. Travels to thoracic spinal cord and out the sympathetic trunk ganglion

Question 32

What do the sympathetic cardiac nerves do?

Answer 32

increase heart rate and force of contraction

Question 33

What is TPR?

Answer 33

All of the vascular resistance offered by the systemic blood vessels

Question 34

What size vessels contribute the greatest resistance?

Answer 34

Smaller vessels such as Arterioles, capillaries, venules

Question 35

Which spinal nerves are responsible for an increase in HR?

Answer 35

T1-4 spinal nerves

Question 36

Why do we not want pulsatile blood pressure?

Answer 36

Because we want smooth, even and consistent blood flow to important parts of the body ie. brain