Monitoring circulatory system

Question 1

What is the function of the nodes in our body?

Answer 1

To send signals to allow the heart the contract -> allow normal beating

Question 2

Why are SA nodes know as pacemakers?

Answer 2

It sets the pace for cardiac activity

Question 3

Where are SA nodes located and do?

Answer 3

generate electrical signals over the 2 atria to contract

Question 4

Where does the electrical signals go?

Answer 4

SA nodes - Atrium - AV nodes - Bundle of his - 2 branches - purkinje fiber

Question 5

What makes the lub sound?

Answer 5

• closing of AV valves as blood is pumping from atria to ventricle
• blood in atria goes to ventricle -> as it fills, AV valves forcefully close so blood does not go backwards

Question 6

What makes the dub sound?

Answer 6

closing of semilunar valves as blood pump from ventricle to arteries

Question 7

What is a stethoscope?

Answer 7

medical device that is used to listen to sound inside body -> heart, lungs or intestine
- one end is vibrating membrane or diaphragm -> connect to hollow, air filled tube

Question 8

What are heart murmurs and what causes them?

Answer 8

• when blood does not flow smoothly in heart
• stenosis -> narrowing in opening of heart valves or arteries
• also when valve close incompletely -> back flow of blood (regurgitation)
• cause heart to work harder to get blood into ventricles

Question 9

What is ECG

Answer 9

Electrical pulse that cause heart to beat and create small charges -> help diagnose heart diseases

Question 10

Voltages and Nodes:

Answer 10

P wave = begins with SA nodes fires and atria contract to move blood
Q = ventricles full with blood
R = Ventricles start to contract + AV valves close
S = ventricles finish contracting and semi opens
T = ventricles relax and aorta/pulmonary artey fill with blood

Question 11

What is blood pressure?

Answer 11

forces blood to exert against walls of blood vessels
- changes in b.p correspond to phases of heartbeat

Question 12

What is systolic?

Answer 12

when ventricles contract and force blood into max. pressure in arteries/aorta -> systole -> allow valves to close

Question 13

What is diastolic?

Answer 13

lowest pressure in arteries when ventricles fill with blood (diastole) -> relaxes

Question 14

How to measure b.p?

Answer 14

with a sphygmomanometer
- wrapped around upper arm and inflated to exert pressure on large artery in arm
- temp. stops flow of blood
- as air is slowly let out, blood begins to flow and pressure of blood against wall of artery is measured
- recorded in mm Hg (normal = 120/80)
- DIASTOLIC B.P, ventricles drop to 0 mm Hg during each heartbeat, BUT in arteries, it never drop so blood keeps flowing

Question 15

What affects b.p?

Answer 15

genetics, activity, stress, body temp, diet, and med
normal increase = from exercise, normal decrease = sleeping

Question 16

What happens when b.p in continuously increases?

Answer 16

causes heart to work harder

Question 17

What is cardiac output?

Answer 17

amount of blood pumped by hear, measured in mL/min
- indicator of level of O2 deliver to body

Question 18

What factors contribute to cardiac output?

Answer 18

1. heart rate = # of heartbeats per min
2. stroke volume = amount of blood forced out of heart with each heart beat
   - equation = heart rate x stroke volume

Question 19

What determines stroke volume?

Answer 19

1. how easily heart fills with blood, related to volume of blood returning to heart from veins and ventricles
2. how readily blood is emptied from heart, related to strength of ventricular contraction and pressure exerted by artery walls

Question 20

What is cardiovascular fitness?

Answer 20

• capacity of heart, lungs, and blood vessels to deliver oxygen to working muscle tissues so they can maintain physical work
• oxygen is used by cell to release energy from good molecules
• provides health benefits by enlargin ventricles; increase elasticity and strengthening ventricle walls -> produce an increase in stroke volume
• length of time it takes heart to recover = less time = more fit heart