circulatory system Flashcards
what does the cardiovascular system do?
transports oxygen, nutrients, hormones, and waste products through the body
what is the process of the circulatory system?
pumps blood from the heart to the lungs to get oxygen. the heart then sends oxygenated blood through the arteries to the rest of the body. the veins carry oxygen-poor blood back to the heart back to the heart to start the process again.
what are common diseases and conditions of the circulatory system?
hypertension (high bp).
atherosclerosis (hardening of the arteries).
coronary artery disease (blood vessels are blocked or narrowed).
heart failure.
arrhythmias (irregular heart rate)
what waste products does the circulatory system help your body get rid off?
carbon dioxide from respiration.
other chemicals by products from your organs
waste from things you eat and drink
what is the process of oxygenated blood getting around the body?
the right ventricle sends low oxygenated blood to the lungs, travelling through the main pulmonary artery.
blood cells pick up oxygen in the lungs.
pulmonary veins carry the oxygenated blood from the hearts left atrium.
the left atrium sends the oxygenated blood into the left ventricle.
what is the role of the veins?
carry deoxygenated blood and carbon dioxide back to the heart which sends blood to the lungs
what does systemic circulation provide?
oxygenated blood to all body tissues.
what does pulmonary circulation provide?
allows for exchange of gases in the lungs.
it carries deoxygenated blood from the right side of the heart to the lungs were oxygen is picked up.
what does coronary circulation ensure?
the heart muscle receives the necessary oxygen and nutrients for its function
what are the 3 main parts of the circulatory system?
heart, blood vessels and blood.
what do valves do?
prevent the backflow of blood
where does the heart receive blood into?
deoxygenated blood goes into the right atrium.
after the heart receives blood in the right atrium where does it go?
pumps it to the lungs for oxygenation through the right ventricle.
after the lungs where does oxygenated blood go?
into the left atrium and to be pumped around the body through the left ventricle.
what last section of the heart does oxygenated blood get pumped through to the rest of the body
left ventricle.
what does the superior vena cava do?
collects blood from the upper body.
what does the inferior vena cava do?
collects blood from the lower body.
what valve does the blood go through to get from the right atrium to the right ventricle?
tricuspid valve
what artery is deoxygenated blood pumped to the lungs by?
pulmonary artery.
what vein is oxygenated blood returned to the heart by from the lungs?
pulmonary vien
from the left atrium what valve does oxygenated blood flow through to get to the left ventricle?
mitral (bicuspid valve)
what artery is used to pump blood to the rest of the body from the left ventricle?
aorta.
what are the 3 types of blood vessels?
arteries, veins and capillaries.
what do arteries do?
carry oxygenated blood away from the heart and towards the bodys tissues and organs.
which artery carrys deoxygenated blood?
pulmonary artery
what are arteries characteristics?
thick elastic walls.
to maintain blood pressure and the smooth flow of blood.
what do veins do?
carry deoxygenated blood back to the heart from the organs.
what are veins characteristics?
thin walls and low pressure
what is the smallest blood vessel out of the 3?
capillaries.
what do capillaries do?
they connect arterioles ( a very small blood vessel that branches off from your artery and carries blood away from your heart to your tissues and organs.)
and venules (very small blood vessels that connect your capillaries with your veins throughout your body.)
what are the capillaries characteristics?
single layer of endothelia cells
what do the thin walls in capillaries allow?
allowing for gaseous exchange, nutrients and waste products between the blood and tissues.
what are the functions of the blood?
oxygen transport, nutrient delivery, immune response, and regulate body temperature.
what does the flow of blood allow?
the delivery of oxygen, nutrients, hormones and immune cells to various tissues and cells
what is plasma?
the liquid component of blood accounting for approximately 55% of its total volume
what does plasma do?
maintains osmotic balance, transports substances and aiding in blood clotting.
what % of plasma is water
90-92%
what are the function of red blood cells?
transport oxygen from the lungs to the tissue and organs and carry co2 back to the lungs for exhalation.
what does red blood cells bind to, to give it its red colour?
hemoglobin
why do red blood cells have a large surface area?
for gas exchange and flexibility to navigate through narrow blood vessels.
what is the function of white blood cells?
they defend the body against infection and substances
is there more red or white blood cells?
red
what do platelets do?
play a crucial role in blood clotting and homeostasis. also contribute towards wound healing and tissue repair
when a blood vessel is damaged what does platlets do?
gather at the vessel and promote the function of a clot to prevent excessive bleeding.
what are the 4 different layers of the heart?
Pericardium:
Epicardium
Myocardium:
Endocardium:
what does the pericardium do?
Protective sac surrounding the heart.
Two layers
Pericardial fluid – lubricates
what is the epicardium
what does it make up?
Outer layer of heart wall
Makes up the visceral layer of serous pericardium
what is the myocardium
what does it contain
Middle layer, largest portion of heart wall
Contains contractile fibres (conduct eletrical impulses),
the conduction system (muscle cells sending signals to cause contraction)
and blood supply
what is the endocardium
Inner most layer smooth muscle that lines the valves and inner chambers of the heart
what are the main properties of the heart?
Rhythmicity- able to depolorise and send impulses
Excitability-ability to respond
Contractility- ability to contract
Conductivity- ability to transmit cardiac impulses
explain the electrical energy in the heart:
when a electrical signal starts, it is generated at the SA node, it then travels down to the AV node, it then passes through the bunble of his in the left and right bundle branches, and then into the purkinje fibres, and then it does it all over again.
what does systole mean in cardiac?
Systole is the period of ventricular contraction.
what is diastole in the cardiac cycle?
Diastole is the period of ventricular relaxation
what happens in disastole?
during diastole the aortic valve is closed, preventing regurgitation of blood from the aorta back into the left ventricle. The mitral valve is open, allowing blood to flow from the left atrium into the relaxed left ventricle. During diastole, the pulmonic valve closes and the tricuspid valve opens as blood flows into the right atrium.
what happens during systole?
After the ventricle ejects much of its blood into the aorta, the pressure levels off and starts to fall. During systole the aortic valve is open, allowing ejection of blood from the left ventricle into the aorta. The mitral valve is closed, preventing blood from regurgitating back into the left atrium. during systole the pulmonic valve opens and the tricuspid valve closes as blood is ejected from the RV into the pulmonary artery.
what does the ‘dubsub’ heart sound produced by
Closing of the AV and semilunar valves produces sounds that can be heard by listening through a stethoscope placed on the chest (tricuspid, mitral pulmonary vein and aortic valve)
what does the ‘lub’ sounds produced by
produced by closing of the AV valves during isovolumetric contraction of the ventricles.
what does the ‘dub’ sound produced by
produced by closing of the semilunar valves when the pressure in the ventricles falls below the pressure in the arteries.
what does stroke volume mean?
Volume of blood pumped by each ventricle in one contraction
Approx. 70ml
what does cardiac output mean? how long? and how do you work it out?
Amount of blood pumped by the heart in one minute
CO = (heart rate [HR]) x (stroke volume [SV])
what is the blood pressure equation
Blood Pressure (BP)
BP = (cardiac output [CO]) x (Total peripheral resistance [TPR])
what is the SA node? where is it and what does it do
main pacemaker
triggers atrial contraction in the right atrium
what is the AV node? what does it do and the location?
allows atrial contract to fill the ventricles, delays signals from the SA node.
right atrium near the tricuspid valve
what is the bundle of his and what does it do?
It is a collection of cells that carry electrical signals from the AV node to the ventricles allowing ventricles to contract in a synchronized manner
what does the right and left bundle branch do?
carry signals to the right ventricle and the left ventricle. to allow them to contract coordinated
what do the purkiijes fibres do?
transmit electrical signals to the hearts ventricles to cause them to contract
explain what happens in the p wave of a ecg?
in the p wave an electrical impulse travels from the sa node to the walls of the atria causing them to contract.
what happens in the PR segement
in the PR segment the impulses reaches the AV node which delays it by 0.1 second
what happens in a Q wave in a ecg?
bundle branches carry signal from from Av node to the heart apex (tip of the hearts left ventricle)
what happen in the QRS segment of a ecg?
the signal spreads through through the ventricle walls causing them to contract.
