A&P Cardiovascular System Flashcards
Define blood pressure
The force exerted by the blood against the artery walls, average value 120/80mmHg
Volume of blood ejected from the left ventricle per minute
Cardiac output (Q)
What does the CCC do?
Controls the cardiac cycle
List 3 benefits of a cool down
Increases venous return
Gradually reduces HR
Prevents blood pooling
Reduces muscular stiffness and soreness
This is the largest cause of death in the western world, caused by a combination of poor diet, high blood pressure and inactivity
Coronary heart disease
What is diastole?
When the heart relaxes, the atria fill with blood
Explain what happens during a heart attack?
A total blockage of a coronary artery, known as a myocardial infarction, which is a consequence of CHD.
What is hypertension?
Long term high blood pressure which accelerates arteriosclerosis, increasing strain on the heart. 140/90
List 3 of the venous return mechanisms
Gravity
Pocket valves
Muscle pump
Respiratory pump
List the path of an impulse through the heart
SA node-> AV node (atria contract)-> bundle if His-> left/right bundle branches -> Purkinje fibres (ventricles contract)
What is Starling’s Law?
Stroke volume is dependent on venous return. An increase in venous return causes an increase in stroke volume.
What is the main function of the vasomotor control centre (VCC)?
Controls the vascular shunt- where blood is moved around the body
What is happening during ventricular systole?
The ventricles are contracting, squeezing blood to the lungs and the body
Contraction of the atria is called ______________
Atrial systole
Where is the cardiac impulse generated?
The Sino-atrial (SA) node
What does the Atrio-ventricular (AV) node do, and why?
Delays the cardiac impulse which allows the atria to finish contracting before the ventricles begin.
What is venous return?
The return of deoxygenated blood to the heart
This condition could lead to blood clots
Atherosclerosis
Define arteriosclerosis
Loss of elasticity in the blood vessel walls which reduces their ability to regulate blood pressure
This is a general term for all diseases relating to the coronary blood vessels and heart muscle
Coronary heart disease
What is angina?
A partial blockage of a coronary artery causing chest pain
What is the most common cause of CHD involving a narrowing of the arteries caused by a build up of fatty deposits
Atherosclerosis
This stimulates the SA node to increase heart rate (HR) and stroke volume (SV)
Accelerator nerve
Blood vessel which transports oxygenated blood away from the heart to the
tissues
Arteries
What is atrial diastole?
Relaxation of the atria
What is atrial systole?
Contraction of the atria which forces remaining blood into the ventricles
Define viscosity
The resistance to blood flow, how thick, or sticky it is
Define bradycardia
A resting heart rate below 60bpm
Describe the cardiac cycle
Events of one heart beat. The atria contract together and force blood into the ventricles (diastole) which then contract (systole) and force blood out of the heart to be pumped around the body
This is an increase in the size of the heart muscle
Cardiac hypertrophy
What is cholesterol?
Blood lipids that can be deposited on arterial walls leading to atherosclerosis
This is blood flow to and around the cardiac muscle
Coronary circulation
What is EDV?
End diastolic volume- the amount of blood remaining in the ventricles after diastole (relaxation)
What is ESV?
End systolic volume- the amount of blood remaining in the ventricles after systole (contraction)
These are ‘Scavengers’ which remove cholesterol from the arterial walls
HDL’s (High density lipoproteins)
What does intrinsic control mean in terms of heart rate regulation?
Internal factors of temperature and venous return that affect HR control
What do LDLs (low density lipoproteins) do?
These deposit harmful blood lipids/cholesterol on the arterial walls
Describe the neural control structures of the CCC
Sensory receptors that provide the cardiac control centre with information:
proprioceptors= motor activity/movement,
chemoreceptors=chemical changes,
baroreceptors= pressure changes
What is OBLA?
Onset of blood lactate accumulation. The point at which production of lactic acid exceeds its removal which causes muscle fatigue
This system initiated by the cardiac control centre decreases heart rate via the Vagus nerve-
Parasympathetic nervous sytem
What is the sympathetic nervous system?
System initiated by the cardiac control centre to increase heart rate, via the accelerator nerve
The redistribution of cardiac output between the organs and muscles from rest to exercise is called
Vascular shunt
What is the WHO?
The World Health Organisation recommend how to achieve a balance active healthy lifestyle
What does BAHL stand for?
Balanced active, healthy lifestyle consisting of regular activity and a healthy diet
Describe the journey of a RBC from the left atrium around the body
Left atrium -> left ventricle -> aorta -> (arteries-> arterioles -> capillaries) -> tissues (gas exchange) -> (capillaries -> venules -> veins) -> vena cava -> right atrium -> right ventricle -> (pulmonary artery-> capillaries) -> lungs (gas exchange) -> (capillaries -> pulmonary vein) -> left atrium
Maximum heart rate is calculated by ______
HRmax= 220-age
At rest:
Average stroke volume is ___ml per beat
Average EDV is ____ml per beat
Average ESV is ____ml per beat
SV= 70ml per beat EDV= 130ml per beat ESV= 60ml per beat
Average Cardiac output (Q) at rest is
5 litres/min
Average resting heart rate is
72bpm
The anticipatory rise which increases heart rate prior to exercise is caused by the release of
adrenaline
During exercise, stroke volume can increase from a resting value of 70ml per beat to a value of _____
between 120-140ml per heartbeat
During exercise, cardiac output (Q) can rise from a resting value of 5 l/min to _____
between 20-40 l/min
Cardiac output= ________ x ________
Stroke volume x heart rate
When intensity of exercise reaches _____ stroke volume plateaus, and any further increase in cardiac output must result in an increase in _________
40-60%
Heart rate
The space in the middle of a blood vessel is called the
lumen
What is blood pooling?
When there is insufficient venous return and blood gathers in the tissues, causing swelling
During exercise what % of blood is shunted to the muscles?
80%
Name 2 ways that blood shunting around the body takes place.
vasodilation and vasoconstriction (controlled by the vasomotor tone)
precapillary sphincters
The CCC is controlled by the _________ Nervous System, which determines the rate at which the SA node sends out impulses.
Autonomic
Name the 4 parts of the blood
Erythrocytes
Leukocytes
Platelets
Plasma
Dissociation means
To release or get rid of
True or false:
97% of O2 transported in the blood is carried by haemoglobin (Hb), packed with RBC’s.
True
Name 3 ways that efficient transport of O2 and CO2 help the performer?
Prolongs the duration of aerobic activity (and anaerobic to a smaller extent)
Delays anaerobic threshold which,
Increases possible intensity/work rate for the activity
Speeds up recovery during & after exercise
Systolic blood pressure can raise up to a maximum of _____mmHg during exercise
250
What happens to blood pressure during heavy weight lifting?
Lifting heavy weights or isometric work = sustained muscle contractions = blocked blood vessels = restricted blood flow = increases vascular resistance
How can exercise help to improve blood pressure over time?
Systolic= Decreases blood pressure temporarily below pre-exercise levels for up to 12 hours.
Diastolic= Remains low for hours afterwards
Exercise can lower BP on a daily basis
Give 2 ways that a healthy active lifestyle can impact blood pressure
Prevents high BP indirectly by reducing the risk of obesity
Exercise also been strongly linked with stress reduction = keep blood pressure at moderate levels
Endurance training can reduce the risk of developing high BP.
How does the heart adapt to regular strenuous training?
HYPERTROPHY (increased heart muscle size) = decreases resting HR by increasing SV to maintain same CO (q) at rest.
A healthy/more efficient heart (bradycardia) is under less stress at rest & over a lifetime = slows down hearts deterioration may improve individuals quality of life.
