The Circulatory System Flashcards Preview

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Flashcards in The Circulatory System Deck (30):

Why do we have a double circulatory system?

One pumps deoxygenated blood to the lungs to take in oxygen and the other pumps oxygenated blood around the body to give up its oxygen to the body cells


How does the heart pump blood around the body?

It's contracts


How many chambers does the heart have?



Name the 4 chambers of the heart

Right atrium, right ventricle, left atrium and left ventricle


Where does the blood which flows into the atriums come from?

The vena cava or the pulmonary vein


When the atriums contract, where does the blood go?

Into the ventricles


When the ventricles contract, where does the blood go?

The pulmonary vein or the aorta and out of the heart


What does the blood flow to the organs through?



What does the blood flow through when it returns to the heart?



How many types of blood vessels are there?



What is the function of an artery?

To carry blood away from the heart


What is the function of a capillary?

They're involved in the exchange of materials at the tissues


What is the function of a vein?

To carry blood to the heart


How is an artery adapted?

The walls are strong and elastic to withstand pressure and they have layers of muscles to keeps them strong with elastic fibres to allow them to stretch and spring back


How is a capillary adapted?

They're really small so they can get to every cell, they have permeable walls do diffusion can happen and they are only one cells thick so this increases the rate of diffusion


How is a vein adapted?

Less thick walls because not as much pressure and valves to help keep the blood flow in the right direction


What are the 4 main things in the blood?

Red blood cells, white blood cells, platelets and plasma


What do red blood cells do and why are the good at this?

The carry oxygen - they have a doughnut shape giving them a large surface area for absorbing more oxygen, they don't have a nuclear do more space for oxygen and they carry haemoglobin


What is haemoglobin?

A red pigment which combines with oxygen in the lungs to make oxyhemoglobin and in body tissues the oxyhemoglobin splits up into haemoglobin and oxygen into release oxygen into the cells


What do white blood cells do and why are the good at this?

Defend against disease - they change shape to engulf microorganism and produce antibodies and antitoxins


What do platelets do and why are the good at this?

Help blood clot - they are small fragments of cells which help the blood to clot at wounds


What does plasma do and why are they good at this?

Carries everything in the blood - carries red and white blood cells, platelets, nutrients, carbon dioxide, urea, hormones, antitoxins and antibodies


What is coronary heart disease?

A disease where the arteries that supply blood to your heart get blocked by fatty deposits which makes the arteries narrow and restricts blood flow which can result in a heart attack


What can you do to resolve this?

Insert stents into the arteries


What do stents do?

Keep the arteries open do blood can pass through


What are the advantages of stents?

They lower the risk of a heart attack


What are the disadvantages of stents?

Over time the artery can narrow again which makes the stent irritate the artery so scar tissues grows, and the patient has to take drugs to stop blood clots


What is artificial blood?

A blood substitute which is normally a salt solution (saline) which is used to replace blood which has been lost and help keep people alive and allow them to replace their red blood cells


What are the advantages of an artificial heart?

Less likely to be rejected by body's immune system and reduces need for heart donors


What are the disadvantages of an artificial heart?

Surgery to fit it can cause bleeding and infection, artificial hearts don't work as well as natural ones, it can fail, blood doesn't flow as smoothly so can lead to strokes and patient had to take blood thinking drugs