Cardiovascular System Noadswood Science, 2012

Cardiovascular System To know the pathway of oxygen through the circulatory system Wednesday, August 12, 2015

Pathway Have a look at the following anagrams - merit for the first to get them all (written down)! –Threa –Reeisart –Pillaarisce –Sinev –Nxyoge –Boncar Ddiioxe –Bicroeana –Tionaripser –Bicroea –Threabngi Heart Arteries Capillaries Veins Oxygen Carbon Dioxide Anaerobic Respiration Aerobic Breathing

Circulation What is the function of the circulatory system? What does it transport? The circulatory system is the body's main transport system, carrying food and oxygen to the cells and taking waste products (carbon dioxide) away It consists of the heart; arteries; veins; and capillaries

Circulatory System

Oxygen Oxygen is initially absorbed into the blood within the lungs (via diffusion) It will now travel through a variety of systems in order to get to the cell, where it is needed for respiration

Traveling Blood travels through three types of vessel - arteries, veins and capillaries with have specific properties: - –Arteries are thick-walled muscular tubes which carry blood away from the heart - fast flowing! –Veins are thin walled tubes which carry blood back to the heart – they have a large diameter and valves as the blood flows slower –Capillaries are extremely narrow tubes which carry blood through our tissues: their walls are just one cell thick - so thin that oxygen, food and waste products can easily pass through them

Blood Vessels – Artery thick outer wall thick inner layer of muscle and elastic fibres narrow central tube (lumen) Arteries are thick-walled muscular tubes which carry blood away from the heart - fast flowing!

Blood Vessels – Veins Veins are thin walled tubes which carry blood back to the heart – they have a large diameter and valves as the blood flows slower thin outer wall thin inner layer of muscle and elastic fibres wide central tube (lumen)

Blood Vessels – Capillaries Capillaries are extremely narrow tubes which carry blood through our tissues: their walls are just one cell thick - so thin that oxygen, food and waste products can easily pass through them wall only one cell thick

Blood Vessels blood from the heart blood to the heart carries blood to and from the body’s cells Artery Carries blood away from the heart Vein Carries blood back into the heart

Blood Blood is a liquid tissue whose function is to fight disease and to transport materials around the body Blood plasma (liquid) containing glucose, amino acids, nutrients, hormones, as well as waste materials like urea Red blood cells contain haemoglobin, a protein which picks up oxygen molecules in the lungs White blood cells fight disease by making antibodies and fighting germs Platelets are cell fragments. Together with fibrinogen they form clots to repair cuts or tears in nearby tissue

Blood Plasma Blood plasma is the liquid which carries everything in the blood (a pale straw-coloured liquid) Red and white blood cells; nutrients such as amino acids and glucose; carbon dioxide; urea; hormones; antibodies and antitoxins are all carried in the blood plasma

Red Blood Cells Red blood cells carry oxygen from the lungs to all the cells in the body – they have a doughnut shape to maximise their surface area and they contain no nucleus at maturity They contain the red pigment haemoglobin which combines with oxygen at the lungs (becoming oxyhaemoglobin) In body tissues the oxygen and haemoglobin split (which releases the oxygen to the cells)

White Blood Cells White blood cells defend against disease – they can change shape to consume unwelcome microorganisms (they do contain a nucleus) White blood cells also produce antibodies to fight microorganisms and antitoxins to neutralise any toxins produced by harmful microorganisms

Platelets Platelets are small fragments of cell and have no nucleus They help the blood to clot at a wound stopping blood loss (and microorganisms entering) A lack of platelets can cause excessive bleeding and bruising

Heart What do you know about our heart? How does it work? How is it specialised? The heart pumps blood around the body – in humans this is a four chambered pump The right side of the heart pumps deoxygenated blood to the lungs to pick up oxygen The left side of the heart pumps the oxygenated blood from the lungs around the rest of the body (which is why it is more muscular)

Heart The right side of the heart pumps deoxygenated blood to the lungs to pick up oxygen The left side of the heart pumps the oxygenated blood from the lungs around the rest of the body (which is why it is more muscular)

Heart body’s cells lungs Oxygenated blood returns to the heart through the pulmonary vein Oxygenated blood is pumped at high pressure from the heart to the body through the aorta Deoxygenated blood returns to the heart through the vena cava Deoxygenated blood is pumped from the heart to the lungs through the pulmonary artery

Double Circulation The pulmonary circulation carries: - –Deoxygenated blood from the heart to the lungs –Oxygenated blood back from the lungs to the heart, ready to be pumped out to the body lungs The systemic circulation carries: - –Oxygenated blood to the rest of the body through the arteries –Deoxygenated blood back to the heart through the veins body’s cells

Cells Oxygen and glucose leak out of the capillaries and the cells close by absorb the required oxygen and glucose The waste products (including carbon dioxide) pass out of the cells and into this fluid, that is then re-absorbed by the blood Capillaries do not join up to every cell - instead fluid is passed out of them, with cells close by absorbing what they need

Summary Oxygen enters the body in the lungs, via breathing It is absorbed into the blood, where it passes through the heart and then throughout the body (via the circulatory system) It travels through arteries, veins and capillaries Cells and blood exchange materials in the fluid, which is released adjacent to the capillaries The cells then use this oxygen for respiration

Stents Stents keep arteries open (tubes inserted inside arteries keeping them opening allowing blood to pass) Stents lower the risk of a heart attack, especially for individuals who suffer coronary heart disease (fatty deposits blocking the blood supply to the heart)

Worksheet Match the circulatory key words with their function

Worksheet Complete the circulatory system worksheet Arteries Heart Veins Capillaries One cell thick

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