Cardiac system Flashcards
Define diastole
The relaxation phase of the cardiac cycle. This is where the ventricles fill with blood.
Define systole
The contraction phase of the cardiac cycle. This is where the ventricles contract and the blood is pumped through and out of the heart.
Define stroke volume
The volume of blood that leaves the heart in a single contraction.
Define health
A state of mental, physical and social well-being and not merely the absence of disease and infirmity/injury.
Define fitness
The ability to meet and cope with the demands of the environment.
Define physical activity
The ability to be active and take part in exercise, which benefits an individual’s physical, mental and social well-being.
Define heart rate (HR)
The number of times the heart beats per minute.
Define anticipatory rise
A slight increase in heart rate usually just before physical activity due to expectation to exercise (adrenaline/anticipation.)
Define cardiac output (Q)
The amount of blood the heart pumps out (measure in L/min.)
What is the equation for working out cardiac output?
cardiac output = stroke volume x heart rate
Q (L/min) = SV (L) x HR (bpm)
How does exercise improve your physical health?
- decreased resting heart rate due to hypertrophy of the cardiac muscle (can pump out more blood in a single contraction.)
- more red blood cells developed (more oxygen able to be transferred around the body.)
- stronger lungs
less risk of developing diseases like CV disease, type 2 diabetes, metabolic syndrome, some cancers - influences life span
- increased metabolism + more energy used to repair muscles etc
What are the differences between trained and untrained individuals?
Trained:
- high altitude training = more red blood cells + haemoglobin than untrained people
- endurance training = cardiac hypertrophy + increase in chamber size = bigger SV = bigger Q = decrease in resting HR
- trained SV = 130-150ml
- endurance SV = 180 ml
- trained = bradycardia (resting HR <60 bpm)
- lower resting HR, lower HR sub-max, slower HR increase, faster return to resting HR
Untrained:
- genetic factors can make you particularly good at sport (however can be improved by training)
- untrained SV 112ml
- untrained / average HR = 70 bpm
Recite the pathway of blood
1 deoxygenated blood returns to the heart, through the VENA CAVAE…
2 blood fills the RIGHT ATRIUM before going through the…
3 TRICUSPID VALVE and into the…
4 RIGHT VENTRICLE which pumps the blood through the…
5 PULMONARY SEMILUNAR VALVE to prevent backflow and the blood carries on travelling through the…
6 PULMONARY ARTERY, out of the heart, towards the…
7 LUNGS to deposit any CO2 and to collect any O2 to bring back to the heart, through the…
8 PULMONARY VEIN, which takes the newly oxygenated blood to the…
9 LEFT ATRIUM, before travelling through the…
10 BICUSPID VALVE and into the…
11 LEFT VENTRICLE, where the blood fills up and cardiac muscle forces the blood through the…
12 AORTIC SEMILUNAR VALVE so there is no backflow and the blood can continue moving to the…
13 AORTA and out into…
14 the rest of the BODY to the WORKING MUSCLES.
Recite the order of the cardiac conduction system
1 the SAN fires, which causes…
2 ATRIAL SYSTOLE, which is the contractions of the atria and this then triggers the…
3 AVN TO FIRE, carrying the electrical impulse to the…
4 BUNDLE OF HIS and then this impulse diverges into the…
5 BUNDLE BRANCHES so that there is electricity running in both sides of the heart. Once this travels up the branches, the impulse comes into contact with the…
6 PURKINJE FIBRES and as soon as this happens, this triggers…
7 VENTRICULAR SYSTOLE and that is when the final contraction occurs, so the blood can leave the heart.
Define cardiac cycle
The mechanic event of one heartbeat