cardiovascular system Flashcards
how do you label the heart
describe the flow of blood through the heart
starts at the pulmonary veins and finishes at the pulmonary arteries
.
describe the cardiac conduction system SAABPV
the body, stimulates the sinoatrial node, this creates an impulse, that cause atria systole. the impulse, then passes through the atrioventricular node, there is a 0.1 delay to allow systole to occur, thus allowing the heart to fill with blood, before the impulse is sent down the bundle of his, to the septum, then i goes through the purkinje fibres, to cause the ventricles to contract (ventricular systole)
what is the role of the sympathetic nervous system
the role of this system, is to increase the heart rate, thus allowing more oxygen to reach the muscles.
the role of the parasympathetic nervous system
is to return the heart rate back to a normal resting level
where is the cardiac control centre located
in the medulla oblongata.
what is the role of chemoreceptors
to detect a change in the carbon dioxide levels in the blood (PH change) if there is an increase in carbon dioxide, then the sympathetic nervous system will be stimulated in order to increase the heart rate.
what is the role of baroreceptors
the respond to a change in pressure, when there is an increase, in pressure the baroreceptors will stretch, this will cause the parasympathetic nervous system to be simulated in order to slow heart rate down.
what is the role of proprioceptors
they are located in muscles, and their role is to simulate the sympathetic nervous system via the AVN, when there is a change in the muscle length, in order to pump more oxygenated blood to the muscles during excersice.
the hormonal control system
- this is where adrenaline is released by the sympathetic nervous system to stimulate the SAN,
- this will help to increase both the speed and force of contraction,
- thus resulting in more oxygenated blood being pumped to the muscles, so they can respire quicker, during excerisce.
stroke volume
is the amount of blood pumped out of the ventricle per contraction
cardiac output
is the amount of blood that is pumped out of the heart per minute and is calculated by multiplying the heart rate and stroke volume together.
heart rate
the number of times, that the heart contracts per minute
venous return
the amount of blood, that is returning to the ventricles during exercise if -> then stroke volume will ->
myogenic
the electrical impulse that the heart generates
what is cardiac hypertrophy ( REMEBER THE HEART IS A MUSCLE)
the training of the heart, in order to increase the size of it, to increase the force of contraction (stroke volume)
bradycardia
when someone has a resting heart rate that is lower than 60bpm (at resting)
atherosclerosis
occurs when the arteries harden and narrow as they become clogged up by fatty acid deposits
atheroma
a fatty acid deposit found in the inner lining of an artery
angina
chest pain that occurs, when the blood supply through the coronary arteries to the muscles of the heart is restricted
what are low density lipoproteins (LDL)
they transport cholesterol in the blood to the tissue and they are classed as bad cholesterol
what are high density lipoproteins (HDL)
- transport excess cholesterol in the blood back to the liver where it is broken down.
- these are good cholesterol due to lowering the risk of heart diseases.
cardiac drift
the principle that once you reach a certain rate of exercise, the stroke volume starts to decrease due to the heart rate increasing, meaning that there is not as much time for the heart to fill with blood however, due to the heart rate increasing whilst the stroke volume increases, this means that we see little to no change in the cardiac output.
pulmonary
deoxygenated blood from the heart to the lungs and oxygenated blood back to the heart.
systemic
oxygenated blood to the body, from the heart and then the return of deoxygenated blood from the body to the heart.
what is the equation for blood pressure
blood pressure = BLOOD FLOW x RESISTANCE
what is the skeletal muscle pump
when muscles contract and relax, the change in shape meaning that they press on near by veins causing a pumping effect to squeeze blood to the heart.
what is the respiratory pump
- when muscles contract and relax during breathing in and out, pressure changes occur in the thoracic (chests) and abdominal (stomach) cavities.
- these changes in pressure compress the nearby veins and assists blood return to the heart.
what are the pocket valves
they, are a valve, that opens as blood flows one way then closes, in order to stop the backflow of the blood.
what are the other factors effecting venous return other than
- pocket valves
- respiratory pump
- skeletal pump
- a thin layer of smooth muscle in the wall of veins, helping to squeeze blood back to the heart
- gravity helps the blood return to the heart from the upper body
- the suction pump action of the heart
what is anticipatory rise
the rise in heart rate, caused by the release of adrenaline, to ensure that oxygenated blood is being pumped to the muscles, prior to exercise.
haemoglobin
an iron - containing pigment, found in red blood cells that combines with oxygen to form oxyhaemoglobin.
plasma
fluid part of the blood (mainly water) that surrounds the blood cells and transports them.
myoglobin
is an iron - containing pigment, that is present in the slow twitch muscles fibres, and it has a higher affinity for oxygen than haemoglobin.
what is the oxyhaemoglobin dissociation curve
the idea, that the graph moves to the right, due to during exercise there being a lower percentage of oxygen saturation in the haemoglobin, due to moving into the myoglobin in the muscle tissue due to it having a higher affinity for oxygen.
what is the Bohr shift
when an increase in blood carbon dioxide and a decrease in pH results in a reduction of the affinity of haemoglobin for oxygen.
what effect does an increase in blood temperature have?
when blood and muscle temperature increases during exercise, oxygen will dissociate from haemoglobin more readily.
what effect the partial pressure of carbon dioxide increasing have?
as the level of blood carbon dioxide rises during exercise, oxygen will dissociate faster from haemoglobin.
what effect does a a change in pH have to the Bohr shift
more carbon dioxide will lower the pH in the blood. A drop in blood pH will cause oxygen to dissociate from haemoglobin more quickly (Bohr shift)
why does the body redistribute blood around the body
in order to provide the working muscles with more oxygenated blood due to the key organs in the body not needing as much oxygen when exercising meaning that the blood can be shunted (redistributed) to the key areas of the body)
what two methods control blood flow
(it links to the widening and narrowing of blood vessels)
vasodilation ( widening of blood vessels) and vasoconstriction (narrowing of blood vessels)
what is redistribution of blood flow important for state 4 reasons
- increase the supply of oxygen to the working muscles
- remove waste product’s from the muscles, such as carbon dioxide and Latic acid
- ensure more blood goes to the skin during exercise to regulate body temperature
- direct more blood to the heart as it is a muscle and requires extra oxygen during exercise
what is Arterio - venous difference
the difference, between the oxygen content of the arterial blood arriving at the muscles and the venous blood leaving the muscles
why do we see a plateau in heart rate, as excersice intensity increases
to give time for the heart, to fill with blood, before contacting again
what is heart range
the difference between your resting heart rate and you maximum heart rate
what is athletes heart
where the heart is bigger than normal
what is the pulmonary system
the blood vessels supplying the heart and lungs
what is the systemic system
the blood vessels supplying the heart and body
compare the structure of veins, arteries and capillaries
why does oxygen bind to Haemoglobin
to from oxyhaemoglobin, to provide the muscles with oxygenated blood.
what are the Pre - capillary sphincter
tiny rings of muscle, located at the opening of capillaries
what is Arterio - venous difference
difference in the amount of oxygen between your artery and veins
mitochondria
- often referred to as the powerhouse of the cell, as respiration and energy production, occur there.
where does the cardiac control centre send impulses
to the Sino atrial node
what nerve controls the heart (parasympathetic)
the Vagus nerve
what nerve controls the heart (sympathetic)
the Accelerator nerve
what type of control involves the medulla oblongata
neural control
what is starlings law
increased venous return -> greater diastolic filling of the heart -> cardiac muscle stretched -> more force of contraction -> increased ejection fraction.
Cardiac conduction system diagram
