Ch 19 Transport in Human 1

You need to know…… Lymphatic system ABO blood groups Composition of bloodRhesus FactorBlood pressure Pulse Coronary arteries & veins supplying the heart muscle Role of muscle and valves in heart and blood vessels Structure of the heart & path of blood path through it Pulmonary & systemic circulation and portal systems Arteries, arterioles, veins, venules and capillaries The way a closed circulation system is organised 2

To survive what do cells need? Food and Oxygen A single celled animal like the amoeba, gets its food and oxygen by allowing materials to move across its cell membrane. In large animals most cells are not close to the surface of the body so they would not get supplies quick enough. So how does the food and oxygen get as far down as your Big toe?

Hence they need a transport System Circulatory System 1.Open Circulatory System Heart pumps blood into vessels that are open ended eg in Insects

2.Closed Circulatory System Blood remains in a continuous system of blood vessels, from which nutrients can diffuse eg in Humans. Arteries carry blood away from the heart to the body organs, while veins carry blood from the organs to the heart. Arteries and veins are linked by a network of tiny blood vessels called capillaries.

Advantages of a Closed Circulation System 1. Blood can be pumped faster Therefore nutrients can be delivered faster to cells allowing the organism to be more active 2. Blood flow rate to different organs can be changed E.g. blood flow can be increased to the leg mucles when running 6

Circulatory System 7

Double Circulation System Blood is first pumped by the heart to the lungs, where it collects oxygen while simultaneously releasing carbon dioxide. Then the oxygenated blood is returns to the heart. The heart pumps this oxygenated blood all around the body. 8

Double Circulation System / Human Two-Circuit Circulation 1.Pulmonary Circuit: heart – to lungs – back to heart 2.Systemic Circuit: heart – to tissues of the body – back to heart 9

Double Circulation System Pulmonary Circuit Systemic Circuit Pumps to the head, trunk and limbs and back to the heart Pumps to the lungs and back to the heart 10

Advantages of a Double Circulation System 1.Separation of oxygen rich and oxygen poor blood 2.Blood pressure can be kept high by the heart 11

Portal systems The Hepatic Portal System carries blood from the intestine to the liver A portal system is one that begins and ends in capillaries 12

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Learning check 1.How does food and oxygen get as far down as your Big toe? 2.What is the Open Circulatory System? 3.What is the Closed Circulatory System? 4.What are 2 advantages of a Closed Circulation System? 5.What is the Double Circulation System? 6.What are 2 advantages of a Double Circulation System? 7.Explain what a portal system is? 14

Main parts of Human Circulation System 1.Heart 2Blood Vessels Arteries 3.Blood Veins Capillaries Arterioles Venules 15

Main Blood Vessels Arteries Veins Carry blood away from the heart Carry blood under high pressure Thick elastic wall Narrow lumen Carry blood towards the heart Carry blood under low pressure Have valves to prevent backflow Thin wall Wide lumen 16

Blood vessels under the microscope Thick Wall Arteries Veins Narrow lumen Thin Wall Wide lumen Have valves to prevent backflow 17

Smaller Blood vessels Arterioles Arterioles connect arteries and capillaries Venules Venules connect capillaries to the veins Capillaries Tiny blood vessels linking arterioles and venules The thin wall allows easy exchange of materials with cells 18

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Cross section of blood vessel Collagen Muscle and Elastic fibres Endothelium Lumen 21

Learning check 1.What are the 3 main parts of Human Circulation System? 2.Name 5 Blood Vessels. 3.Give 4 features of Arteries. 4.Give 5 features of Veins. 5.Name 3 Smaller Blood vessels. 6.Give a features of each. 22

Pathway of blood Around Body 23

The Heart Is a strong double pump made of cardiac muscle, surrounded by a special membrane sac - pericardium to prevent friction. Found between the lungs, slightly to the left side in the thoracic cavity. The right & left halves are divided by the septum. Each half consists of 2 chambers: 1.the atrium 2.the ventricle 24

Each half is separated by a valve: 1.The Tricuspid valve on the right - Prevents backflow into right atrium when the right ventricle contracts. 2.The Bicuspid Valve on the left - Prevents backflow into left atrium when the left ventricle contracts. 25

Blood supply to the heart wall The heart has its own blood supply from the coronary arteries (oxygen & nutrients) which come from the aorta & the coronary veins (carbon dioxide & wastes)which empty into the vena cava. 26

Vena Cava Right Atrium Tricuspid Valve Right ventricle Left Ventricle Left Atrium Pulmonary Vein Aorta Pulmonary Artery Bicuspid Valve Septum Cardiac muscle Semi Lunar Valves 27

Blood pathway through heart Right Atrium Tricuspid valve Right ventricle Left atrium Bicuspid valve Left ventricle Vena Cava Pulmonary arteryAorta Pulmonary vein 28

Valves Semi Lunar valves Tricuspid valve Bicuspid Valve Prevent backflow into heart Prevents backflow into left atrium Prevents backflow into right atrium 29

Learning check 1.The heart is a pump made of what muscle? 2.The heart is surrounded by a special membrane? 3.The heart is found in what cavity? 4.The heart is divided by the? 5.Each half consists of 2 chambers called? 6.Each half is separated by valves called? 7.The heart has its own Blood supply, explain? 30

Heartbeat and its control The heart beat consists of alternate contraction and relaxation of the cardiac muscle The heart beat is controlled by the pacemaker The pacemaker / SA node is a specialised knot of muscle embedded in the top wall of the right atrium 31

The pacemaker / SA node The pacemaker / SA node: 1.sends out waves of impulses (electrical signals) 2.which causes the artium to contract (atrial systole) 3.the impulse wave reaches the AV node (specialised knot of muscle embedded in the bottom wall of the right atrium) 4.which coducts the waves of impulses from the artium to the ventricles, 5.Causing them to contract (ventricular systole). 32

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Heart Song 36

Pulse A pulse is a wave of vibration that passes down the walls of arteries when the aorta expands following the contraction of the left ventricle. The alternate expansion and contraction of arteries can be felt in the wrist / neck. Average pulse rate is 72 beats per minute 37

Blood Pressure Blood Pressure is the force of blood pushing against the wall of a blood vessel Blood is forced into arteries under pressure from the left ventricle, the region of highest pressure And eventually comes back to the heart in the right atrium, the region of lowest pressure 38

Blood Pressure Human blood pressure is taken from the artery in the upper arm. It is measured with an instrument that records the pressure it takes to stop the blood flow through this artery. 39

Effect of smoking on the circulation system 1.Nicotine increases the heart rate, blood pressure & the amount of cholestrol in the blood. These puts a bigger workload on the heart. 2.Carbon monoxide reduces the amount of O 2 carried by the blood. This reduces energy levels. 3.Other chemicals in tobacco, increase the chance of clots. 40

Effect of Diet on the circulation system High salt intake High intake of fat causes a build up of cholesterol Cholesterol may block arterioles and lead to stroke or heart attack Raises blood pressure which can cause heart attack 41 Clotting of artery

Effect of Exercise on the circulation system Exercise increases our ability to transport oxygen Exercise strengthens the heart This improves circulation This gives increased energy levels 42

Learning check 1What causes the blood to be under pressure in the arteries ? 2Explain the term Pulse 3What controls the rate of heartbeat 4Give two harmful effects of cigarette smoke on the circulation system 5Explain why salt can have a negative effect on the circulation system 43

Lymphatic System A secondary transport system consisting of one way system of vessels that collects and returns excess tissue fluid to blood system 1.Lymph vessels 2.Lymph Nodes 3.Lymph Structure 44

Lymph vessels & blood vessels 45

LymphatIc SystemLymphatIc System 46

Lymphatic System Functions 1.Collect tissue fluid and return it to the blood system 2.Fight Infection by 3.Transport digested fat away from intestine (a) Filtering out microorganisms in the lymph nodes (b) Destroying microorganisms by antibody production (c) Mature and store lymphocytes 47

Learning check 1Name the three main parts of the Lymphatic System 2Name three substances dissolved in plasma 3Name a blood grouping system other than the ABO System 4What is the function of white blood cells 5Give two functions of the Lymphatic System 48

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