Cardiovascular System PDF

THE CARDIOVASCULAR SYSTEM CLIP https://www.youtube.com/watch?v=OkgIP70rj90 CARDIO-RESPIRATORY SYSTEM Cardiovascular System - consists of the heart and blood vessels o It keeps the blood circulating through the body o Respiratory System - consists of the lungs and air passages. It removes...

THE CARDIOVASCULAR SYSTEM CLIP https://www.youtube.com/watch?v=OkgIP70rj90 CARDIO-RESPIRATORY SYSTEM Cardiovascular System - consists of the heart and blood vessels o It keeps the blood circulating through the body o Respiratory System - consists of the lungs and air passages. It removes carbon dioxide and replaces it with oxygen o Due to their dependence on each other, the two systems are referred to as the Cardio-Respiratory system. HOW DOES THE HEART PUMP BLOOD ▪ https://www.youtube.com/watch?v =ruM4Xxhx32U  THE CARDIOVASCULAR SYSTEM Cardio-vascular system is also known as the circulatory system is made up of the: o Blood o Blood vessels o Heart Its main functions are to: o Deliver nutrients and O2 to cells o Remove waste and CO2 from cells o Maintain an even core body temp (37°C) BLOOD ▪Blood is the fluid that flows through the circulatory system. It contains blood cells, food, minerals and gases that are vital for the bodies functioning. ▪Each person has approximately 4 – 5 litres of blood, which takes about 20 seconds to circulate around the body. Blood is made up of: ▪ Blood cells (45%) ▪ Plasma (55%) BLOOD ▪https://www.youtube.com/watch?v=VSVYgivfs9c FUNCTION OF BLOOD Main functions of blood: ▪Transport oxygen from lungs to tissues ▪Transport carbon dioxide from tissues to lungs ▪Transport waste from tissues to kidneys ▪Transport digested food from small intestines to tissues  COMPONENTS OF BLOOD Blood has 4 main components: ▪RED BLOOD CELLS – contain haemoglobin which carry the oxygen in blood. ▪WHITE BLOOD CELLS – fight against infections in the body. ▪PLATELETS – cells that form blood clots to stop bleeding. ▪BLOOD PLASMA – is 90% water and is the fluid that carries all the cells and nutrients.  BLOOD VESSELS ▪Veins and arteries are the network that carry blood throughout the body. ▪The largest blood vessels are closest to the heart and get smaller as they move towards the outer surfaces of the body. ▪You have approximately 100,000 km of blood vessels in your body, enough to wrap around the Earth 2.5 times. BLOOD VESSELS The body’s blood vessels are made up of: ▪ Arteries ▪ Arterioles ▪ Capillaries ▪ Venules ▪ Veins BLOOD VESSELS: ARTERIES ARTERIES: carry blood away from the heart. They have strong elastic walls. Arteries have a pulse and carry bright red blood full of oxygen (oxygenated). ARTERIOLES: are essentially smaller arteries that then turn into capillaries. BLOOD VESSELS: CAPILLARIES CAPILLARIES: capillaries make a vast network of throughout the body tissues. They are very small, and the walls are usually only one cell thick. They allow nutrients and oxygen into the tissues (muscles) and collect carbon dioxide and waste. BLOOD VESSELS : VEINS VEINS: carry blood back to the heart. Carry dark reddish blue blood that is high in carbon dioxide and low in oxygen (deoxygenated). VENULE: very small veins that collect blood from the capillaries. CHARACTERISTICS OF ARTERIES AND VEINS ARTERIES VEINS Strong elastic walls Carry blood reddish blue in colour include a component of muscle Blood is low in O2 and high in CO2 High pressure of blood in the arteries Walls are thin and less elastic carry blood bright red in colour Have valves inside to prevent backflow of blood Muscles around veins contract to push the blood back towards the heart o Capillaries link arteries to veins. o Allow exchange of nutrients and oxygen into the muscle and CO2 and waste to pass out. BLOOD’S JOURNEY ▪ Blood leaves the heart via the aorta which is the body’s main artery. ▪ After the main arteries the blood then travels through the arterioles. ▪ The blood then moves through the capillary network to deliver oxygen + nutrients and collect carbon dioxide + waste. ▪ From the capillaries the blood then makes its way back to the heart moving through venules and then the veins. IMPORTANT BLOOD VESSELS Blood Vessel Where does it supply blood flow? Pulmonary Artery Pulmonary Vein Lungs Carotid Artery Jugular Vein Brain Brachial Artery Brachial Vein Arms Femoral Artery Femoral Vein Legs IMPORTANT BLOOD VESSELS ▪AORTA: main artery of the body. First artery the blood enters when it leaves the heart. ▪SUPERIOR AND INFERIOR VENA CAVA: The vena cava is the vein that returns the blood the heart.  THE HEART ▪ The heart is a hollow muscular structure made of cardiac muscle. ▪ It is a pump that pushes blood around our body. ▪ It is about the size of your clenched fist. ▪ It is situated between your lungs, behind your ribs. EXPLORING THE HEART ▪https://www.youtube.com/watch?v=-s5iCoCaofc THE HEART ▪ The walls of your heart contract and relax (pump) between 60 – 80 times a minute when resting. This is known as your heart rate. ▪ During a lifetime of 70 years the heart will pump 100 – 150 million litres of blood and it will beat over 2.5 billion times. CHAMBERS OF THE HEART The heart has four chambers: ▪UPPER CHAMBERS ▪ Left atria ▪ Right atria ▪LOWER CHAMBERS ▪ Left ventricle ▪ Right ventricle BLOOD FLOW THROUGH THE HEART ▪Blood comes from the body, via the vena cava, into the right atria. ▪The blood then moves down into the right ventricle and is pumped into the lungs to be oxygenated. ▪From the lungs the blood comes back to the heart into the left atria. ▪The blood moves down into the left ventricle and is then pumped out into the body via the aorta. FLOW OF BLOOD  PULSE ▪A pulse is the pressure wave that occurs when your heart beats (pumps). ▪The pulse travels along the arteries at about 7 metres per second. Main pulse points: ▪ Temporal – temple ▪ Carotid – neck ▪ Radial – wrist ▪ Femoral – groin  BLOOD PRESSURE ▪ As blood is pumped through body it creates pressure within the arteries. This is blood pressure. ▪ Blood pressure is an important health indicator to assess the functioning of the heart, kidneys and blood vessels. MEASURING BLOOD PRESSURE To measure blood pressure, we take two measurements: ▪Systolic = measures the pressure in the arteries when the heart beats ▪Diastolic = measures the pressure in the arteries when the heart is relaxed (between beats) BLOOD PRESSURE Why blood pressure is measured in mm Hg? ▪ The abbreviation mm Hg means millimeters of mercury. Mercury was used in the first accurate pressure gauges and is still used in medicine today as the standard unit of measurement for pressure. Normal Systolic = 120 mmHg Diastolic = 80 mmHg Low Systolic = 80 mmHg Diastolic = 60 mmHg High Systolic = 180 mmHg Diastolic = 100 mmHg  WATCH THIS ▪https://www.youtube.com/watch?v=q0s-1MC1hcE (2 mins) KEY TERMS Cardiac output (Q)- the amount of blood pumped out of the heart in one minute. Q (litres per minute) = HR (bpm) x SV (litres per beat) Stroke volume (SV)- the amount of blood ejected by the left ventricle per beat. Heart rate (HR) - the number of times the heart beats in one minute.  ACUTE CARDIOVASCULAR RESPONSES TO EXERCISE What is the main focus of the Cardiovascular System? During exercise, the cardiovascular system needs to deliver greater amounts of oxygen and energy substrates to the working muscles in order to meet the increasing demands of the activity. The focus is on getting more blood to the working muscles to deliver O2 and speed up the removal of CO2 and other waste products. A more efficient circulatory system doesn’t have to work as hard to provide the same GAMES TO HELP YOU REMEMBER https://www.sciencelearn.org.nz/labelling_interactives/1-label-the- heart https://www.purposegames.com/game/the-heart-quiz