Unit 2 The Circulatory System

Slide 1: Science Interactive LTD Copyright 2005 Science Interactive LTD Multimedia CD-ROM for PC is a collection of 38 units totalling over 1150 PowerPoint slides matched to current single and double Science GCSE syllabuses. Each unit covers a wide range of different delivery and learning styles, offering an exciting way to involve your pupils during lessons or revision sessions. All styles of teaching and learning are supported through use of high quality images, graphics, challenging exercises and questions. Units can be used in the classroom via an interactive whiteboard, data projector or used during individual study via a PC or school network. Full users’ licence is available under our ‘comprehensive package’ or lessons can be purchased separately. Science Interactive LTD. PO BOX 50764 LONDON NW6 9AT email: sales@science-interactive.co.uk web: www:science-interactive.co.uk GCSE SCIENCE Unit 1: The Digestive System Unit 20: Crude Oil and its Products Unit 2: The Circulatory System Unit 21: Rock Cycle OCR Unit 3: Healthy Body and Immunity Unit 22: Elements, Molecules and Compounds EDEXCEL AQA Unit 4: The Respiratory System Unit 23: Ionic and Covalent Compounds Unit 5: Nervous System and the Senses Unit 24: The Halogens, their Uses and Compounds Unit 6: Human Homeostasis Unit 25: The Noble Gases, their Properties and Uses Unit 7: Hormones and the Endocrine System Unit 26: Rates of Reaction Unit 8: Drugs and Bad Body Maintenance Unit 27: Energy Unit 9: Photosynthesis in Green Plants Unit 28: Generating Electricity and its Domestic Use Unit 10: Water Transport in Plants Unit 29: Electricity Unit 11: Flow of Energy and Elements through the Environment Unit 30: Light and the Electromagnetic Spectrum Unit 12: Mitosis and Meiosis Unit 31: Radioactivity Unit 13: Inheritance and Selection Unit 32: Newton's Forces and the Effects of Forces Unit 14: Evolution and Human Impact Unit 33: Earth and Space Unit 15: Genetic Engineering Unit 34: The Earth and Plate Tectonics Unit 16: The Periodic Table and its Elements Unit 35: The Alkaline Earth Metals Unit 17: The Alkali Metals Unit 36: Sound and Hearing Unit 18: Metals and their Properties Unit 37: Natural Forces Unit 19: The Transitional Metals Unit 38: Cells, Tissue, Organs and Organs systems

Slide 3: Unit 2: The Circulatory System Science Interactive LTD Copyright 2005 Understand: Keywords: The role of the cardiovascular system and its key 1. Blood, Tissue, Red blood cells, White blood organs. cells, Platelets, Antibodies, Cardiovascular, That blood is a moving tissue containing blood 2. System, Heart, Arteries, Capillaries, Veins, cells, oxygen, carbon dioxide, nutrients, Oxygen, Transport, Systole, Diastole, hormones and waste products. Haemoglobin, Microbes, Bacteria, Viruses, The role of red blood cells and how haemoglobin 3. Disease, Scab, Immunity, Lymphocytes, aids oxygen transport. Neutrophils, Clotting, Antibodies, Vaccines, The anatomy and function of the heart as a four 4. chambered pump. Vaccination & Arthrosclerosis. The role of arteries, veins and capillaries. 5. The heart cycle including systole and diastole. 6. What lifestyle factors contribute to the 7. development of arthrosclerosis and the key events of a heart attack. That the genetic blood disorder, sickle cell 8. anaemia affects oxygen transport to cells. How maintaining fitness leads to a healthy body. 9. 10. The clotting response and scab formation. 11. The role of white blood cells, platelets and antibodies in protecting us against infection by bacteria and viruses. Click mouse to begin

Slide 4: Science Interactive LTD Copyright 2005 The cardiovascular system The cardiovascular system, like any other organ system is a collection of specialised cells, tissues and organs. Its role is to transport useful substance like o________, amino acids and glucose to respiring tissues whilst removing waste substances like c______ dioxide and urea. Your blood also transports hormones produced by the endocrine glands, for example adrenalin. W______ blood cells, antibodies and platelets are also transported by the blood and help prevent infection caused by viruses and bacteria. Why does a unicellular organism like an Amoeba not need a cardiovascular system ? Overview of the cardiovascular system: Word bank: oxygen carbon white Blood cells Blood vessels Heart Cardiovascular system Diagram Red and white blood Blood vessels range The heart continuously The cardiovascular system Notes cells are transported from almost 1 cm in pumps blood around the is the human body’s around the body by diameter to a fraction body, beating around 70 transport system. It moves network of tubes. of a millimetre. There times a minute for almost oxygen, carbon dioxide, These cells are made are over 50,000 km of 80 years. It is an nutrients, hormones and in the soft marrow of blood vessels in the incredible example of immune cells around a the long bones. human body. bio-engineering. network of tubes.

Slide 5: Science Interactive LTD Copyright 2005 Your blood The human body has about five litres of blood which is continuously p______ around a network of arteries, capillaries and v______. Blood is a moving, liquid tissue that contains many types of cells, each which a unique function. Red blood cells transport oxygen around the body. White blood cells help fight disease. P________ are cell fragments which help scabs to form to prevent bleeding and microbial infection after injury to the skin. The yellow liquid called plasma transports nutrients like glucose and waste products like carbon dioxide and urea. How would you separate the yellow plasma from the red and white blood cells ? Human blood: Word bank: pumped veins platelets Blood volume Transfusions Blood plasma Blood cells Diagram An average human has Blood transfusions are Plasma can also be given One of the specialised Notes five litres or eight pints often performed during surgery or cells of blood is the red of blood circulating during surgery or after following dehydration. blood cell or erythrocyte. around the body. When a major accident. Plasma contains salts, It is highly specialised to you donate blood, Blood is vital for life water, nutrients like sugar transport oxygen around doctors only take one and needs to be and amino acids and the many arteries veins pint or half a litre. replaced quickly if hormones like adrenalin. and capillaries. lost.

Slide 6: Science Interactive LTD Copyright 2005 Red blood cells and their function There are over four million red blood cells in every mm3 of blood. Their function is to transport o_________ from the l______ surface, through the capillary network to every living cell in your body. Red blood cells are well designed to transport oxygen, having no n_________ and a dumbbell shape to increase s_________ area. They are also rich in haemoglobin, which binds oxygen during its transport from the lungs around the entire body. How does having no nucleus help red blood cells to transport oxygen ? Red blood cells: Word bank: oxygen lung nucleus surface What's in blood Blood plasma Red blood cells Haemoglobin Red blood cell Diagram Plasma Platelets Red blood cells A single drop of blood Over half the liquid in Red blood cells contain Red blood cells are rich in Notes contains many millions blood is clear plasma. a red pigment called the protein haemoglobin of red blood cells. This Nutrients from the haemoglobin. They and iron, which transport represent just under digestive system are have no nucleus and are oxygen from the lung half the total number of dissolved in plasma as biconcave in shaped to surface to billions of cells found in human well as waste products help transport oxygen respiring cells in the blood. like urea. around the body. human body.

Slide 7: Science Interactive LTD Copyright 2005 Other components of blood White blood cells are larger than r____ blood cells, but there are fewer of them. For every one white blood cell there are over 500 red blood cells. Their main function is to protect the body against m_______ infection. There are two main types of white blood cells. Lymphocytes produce antibodies which bind bacteria and viruses before there are engulfed by the other type of white blood cell, neutrophils. Platelets, which are not whole cells, help scab formation when you cut your skin. This prevents further blood loss. What is the disease called when your blood fails to clot ? Other components of the blood: Word bank: red microbial Lymphocytes & neutrophils Platelets Other blood components Diagram lym ne ph utr oc op yte hil s s Both lymphocytes and neutrophils are Platelets are not true If you analyse your blood, you will Notes part of the immune system. They roam whole cells, but cell also find dissolved in the plasma the body and ‘search and destroy’ any fragments. When you cut nutrients like glucose, amino acids, invading microbes (bacteria & viruses.) yourself, platelets help fatty acids and glycerol, which are Lymphocyte cells produce antibodies scab formation preventing the products of digestion. Hormones which help clump bacteria together so further blood loss and are also transported from their site they can be engulfed by neutrophils. microbial infection. of production to their target tissues.

Slide 8: Science Interactive LTD Copyright 2005 Arteries, veins and capillaries The heart does not work alone to deliver oxygen and n_______ to the entire body. Blood is pumped around a highly complex system of blood vessels measuring over 50,000 km in the average human. There are three types of blood vessels: Arteries, Veins and Capillaries. Arteries carry blood at the highest pressure away from the h_____ and therefore have the thickest elastic muscle wall of all of the different types of blood tubes. From the descriptions below describe any similarities of differences ? Blood tubes of the cardiovascular system: Word bank: nutrients heart Arteries Capillaries Veins Valve Elastic fibres Elastic fibres Thick muscle Thin muscle Outer wall Outer wall Arteriole Venule Capillaries Arteries carry blood away from the Fine capillaries cover the human Veins carry blood towards the heart heart under high pressure. They have a body in a network of tubes. These under low pressure. They have a thin thick muscle and elastic layer which capillaries are extremely thin and muscle and elastic layer and valves stretch every time the heart beats. They narrow, measuring over 50,000 which prevent blood flowing contract back and force blood forwards. km in the human body. You need backwards. Blood flow back towards This can be felt as your pulse ! a microscope to see capillaries. your heart is also helped by your

Slide 9: Science Interactive LTD Copyright 2005 Blood cells at the capillary Blood capillaries have a very small d______ allowing only one red blood cell through at a time. Blood flows very slowly through your capillaries. The capillaries are extremely thin walled, which allows o______ and plasma which contains nutrients to diffuse to the tissue bed and cells. Also waste products like urea and carbon dioxide can pass from the cells back to the capillary. Why are red blood cells unable pass through the capillary walls ? Understanding your capillaries: Word bank: diameter oxygen Blood capillaries Gaseous and nutrient exchange at the capillary bed Diagram Net pressure Carbon dioxide Urea Wastes Glucose Water Oxygen Amino acids Cells Notes An electron micrograph Oxygen and nutrients including glucose diffuse from the blood, across of a single capillary. the capillary wall to the cells. These are used for cellular respiration. Notice the narrow Waste products including carbon dioxide and urea are transported back diameter allowing only in the plasma for transport to the lungs and kidneys. one blood cell through.

Slide 10: Science Interactive LTD Copyright 2005 Blood circulation The circulation of blood through the heart, lungs and other major organs keeps the human body supplied with the o______ and nutrients that it requires for cellular respiration, growth and repair. This transport system also carries the white blood cells, platelets and antibodies around the body defending us against microbial infection. What lifestyle factors can prematurely age your cardiovascular system ? Circulation in the body: Word bank: oxygen Capillary exchange in detail Red Blood Cell Red Blood Cell CO2 CO2 Tissue O2 O2 O2 O2 Oxygen is exchanged for carbon dioxide at the tissue surface. Oxygen diffuses across the capillary wall into the cells or tissue. Oxygen is combined with glucose during cellular respiration. Waste products including carbon dioxide and urea are transported in the plasma to the lungs and the kidneys.

Slide 11: Science Interactive LTD Copyright 2005 Oxygen transport by blood haemoglobin Red blood cells contain the protein, haemoglobin which is responsible for binding oxygen at the l______ tissue (alveoli) and delivering it to every r____________ tissue or cell via a huge capillary network which can be up to 50,000 km in length in the human body. Haemoglobin also contains the mineral i_____ to help oxygen transport. Why is iron important in the diet and why do females require greater quantities of this mineral ? Oxygen transport: Word bank: lung respiring iron At the alveoli Haemoglobin In the tissues Haemoglobin Diagram O2 O2 CO2 CO2 CO2 O2 O2 O2 O2 O2 Oxyhaemoglobin Notes Air contains 21% oxygen which is Haemoglobin is a protein found Oxygen diffuses across the thin taken to the alveoli tissue by the in the red blood cell. It contains capillaries walls to the cells. It bronchioles. Oxygen dissolves Iron (Fe2+) and is able to bind travels form a high concentration across the thin alveoli surface and oxygen at several sites. Why do inside the capillary to a low binds to red blood cells found females require more iron than concentration. Carbon dioxide inside the lung capillaries. males ? moves to the blood.

Slide 12: Science Interactive LTD Copyright 2005 The human heart The heart, a four chambered pump is a collection of s__________ tissues which work together to pump blood to the lungs, picking up oxygen and excreting carbon dioxide and then to the body delivering oxygen and nutrients to every respiring cell, via a network of arteries, veins and capillaries. The ventricles create sufficient p_________ by squeezing to send blood either to the lungs (right ventricle) or the rest of the body (left ventricle) A number of valves between the connecting chambers stops any unwanted backflow of blood. Why is the left ventricle thicker than the right ventricle ? Main features of the human heart: Word bank: specialised pressure Human heart Heart valves Blood pressure Diagram The human heart is about the size of Valves between the four The difference in blood Notes a adult fist. Its function is to pump chambers (Atria and Ventricles) pressure in the arties and veins blood to the lungs (RA, RV) and to open and close to prevent blood allows blood to flow around the the rest of the body (LA, LV). Look from being forced backed when body. This pressure is created at the picture of the four chambers. the ventricles contract. by the ventricles contracting.

Slide 13: Science Interactive LTD Copyright 2005 The heart cycle one If you look at the diagram below and follow the arrows, you can trace the path of blood around the heart. Deoxygenated blood flows from the b_____, entering the right atria. It then travels to the right ventricle where its is pumped to the l______ to pick up oxygen and excrete carbon dioxide. Oxygenated blood enters the left atria, where it travels to the left ventricle. Here blood is pumped to the rest of the body via the aorta. Circulation around the heart: Word bank: body lungs Arrow Action (Draw numbered arrows on the diagram) Deoxygenated blood enters the heart into the right atrium. 1 Right ventricle contracts and pumps blood to the lung. 2 Blood loses carbon dioxide and picks up oxygen. Lungs Oxygenated blood enters the heart into the left atrium. 3 Blood moves into the left ventricle. 4 Blood is forced through the largest artery and into the blood. 5 Blood delivers oxygen and nutrients to all cells. 6 The diagram above shows the structure of the human heart. The pumping action of your heart is produced by the muscle walls of the left and right ventricles. When the ventricles contract, blood is squeezed at pressure into the arteries that supply the lung or the entire body. The valves only allow blood to flow in one direction. Draw a flow diagram to help explain how blood is pumped around your lungs and body ?

Slide 14: Science Interactive LTD Copyright 2005 The heart cycle two The heart is supplied by electrical impulses through the vagus nerve. At rest, the heart beats approximately 72 beats per minute (b.p.m.) When we e_________, our heart rate increases to supply the exercising muscles with additional oxygen and nutrients. In a trained athlete what are the differences in how their hearts perform during exercise ? The heart cycle: Word bank: exercise Stage One Two Three Four Diagram ECG Notes The beating cycle of the heart lasts just under a second. It is controlled by the vagus nerve. If we monitor the electrical activity of the heart it gives a typical profile as shown left. The peak electrical activity triggers the contraction of the left ventricle, the largest ventricle which forces oxygenated blood around the body.

Slide 15: Science Interactive LTD Copyright 2005 Understanding blood pressure Blood pressure is caused by the ventricular muscles contracting during every heart cycle. This pressure forces blood through the vast network of arteries, capillaries and veins. High blood pressure, caused by narrowed arteries and high salt diets can damage your vascular system and in extreme cases, lead to a heart a______. Blood pressure in humans: Word bank: attack One Two Three Four Blood pressure Diagram You can take your blood pressure. A normal adult should have a reading of 120/80 (mmHg) Notes Pressure (mmHg)

Slide 16: Science Interactive LTD Copyright 2005 The heart and aerobic respiration If you view animals cells under a m__________, you can see tiny dots in the cytoplasm. These are mitochondria. Cellular respiration occurs in the mitochondria, releasing energy from the breakdown of glucose using oxygen. All living things give out carbon dioxide, a waste product of cellular respiration. It is the role of the heart to supply sufficient oxygen to and remove waste carbon dioxide from all cells in the Human body. Respiration and mitochondria: Word bank: microscope Mitochondria Notes Diagram Cellular respiration is the breakdown of glucose with oxygen providing cellular energy. This happens in the C6H12O6 6H2O cell’s mitochondria. Cellular respiration equation: Energy Mitochondria C6H12O6 + 6O2 6H2O + 6CO2 6O2 6CO2 Cells Glucose Oxygen Water Carbon dioxide Muscles Transport Digestion Nerve messages Body temp (oC) Building cells Use Diagram

Slide 17: Science Interactive LTD Copyright 2005 Oxygen debt during anaerobic respiration When muscles are working hard, they begin to respire glucose without oxygen. This is called anaerobic respiration. Lactic acid produced during anaerobic respiration builds up and slowly poisons your muscles. When your body can’t supply sufficient oxygen to your muscles, this is called oxygen debt. When you stop vigorous exercise, your heart and lungs continue to supply extra oxygen to allow the muscle to breakdown l____ acid. This repays the oxygen debt. Oxygen debt: Word bank: lactic Oxygen debt in muscles Lactic acid production in muscle Diagram Oxygen supply 2.5 2.5 Oxygen demand (litres) Oxygen supply (litres) Lactic Oxygen demand C6H12O6 2.25 2.25 acid 2.0 Oxygen debt 2.0 Sugar b 1.75 1.75 1.5 1.5 1.25 1.25 a B C 1.0 1.0 c A 0.75 0.75 0.5 0.5 6O2 Carbon 0.25 0.25 dioxide 0 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Time (Minutes) Notes During rest (a) the supply of oxygen to the muscles meets demand. During anaerobic respiration, less During hard vigorous exercise (b), demand increases above supply energy is produced respiring glucose and the muscle have to continue respiring glucose without oxygen. without oxygen. Lactic acid builds Anaerobic respiration leads to the oxygen debt and formation of up and begins to damage your lactic acid. This oxygen debt is repaid when exercise stops (c) by muscles, giving you the sensation of the lungs continuing to oversupply the muscles with the lungs. the ‘burn.’

Slide 18: Science Interactive LTD Copyright 2005 Complete fitness Athletes require their key organ systems to work together so that they can exercise and play their sport. Fitness is a measure of how well you body w_____ and exercises. Athletes require ‘total fitness’ so that they can win and excel at their s______. The cardiovascular, respiratory and skeletal-muscle system all work together to supply the oxygen and nutrients to your muscles. How would you devise a training programme to increase your overall fitness ? Essential organ systems: Word bank: works sport Athlete Cardiovascular Respiratory Muscle Diagram Professional athletes The cardiovascular Your respiratory system The skeletal-muscle Notes like runners and system is the human is constantly working to system works to move footballers work hard body’s transport system. exchange oxygen for the body during sport. to be fit for their sport, It moves oxygen, carbon carbon dioxide between An elite sprinter but ideas of fitness dioxide, nutrients, the alveoli and the requires the fastest vary according to their hormones, and immune pulmonary capillaries in contracting muscles sport. cells around a network of the lung. during a 100 m race. tubes.

Slide 19: Science Interactive LTD Copyright 2005 Maintaining fitness Athletes work hard to achieve total fitness, but what does being fit mean ? If you are fit, you will have a low resting heart rate which recovers quickly after e_________. Your lungs efficiently exchange oxygen and carbon dioxide at the alveoli tissue and your skeletal m________ system moves you quickly, without tiring during a race or a game. Exercising (running, weights & gym work) helps us to achieve fitness and improve our ability to compete and win. Fitness and the five ‘S’ Word bank: exercise muscle Strength Stamina Skill Suppleness Speed Diagram Notes The five ‘S’ strength, stamina, skill, suppleness and speed are all improved by repetitive training and exercise. Regular exercise also helps prevent people becoming overweight and developing heart disease and diabetes. Nearly 25% of all adults are now considered obese with almost 50% of all pupils of secondary school age not taking enough exercise.

Slide 20: Science Interactive LTD Copyright 2005 Atherosclerosis and heart disease A high f____ diet over many years, lack of e__________, too much alcohol and smoking leads to arthrosclerosis and general heart disease. Arthrosclerosis reduces the diameter of the aorta and other major arteries, therefore increases blood p_______. Eventually a heart attack may follow because of a clot in the coronary arteries. How can we educate people to reduce their risk of developing atherosclerosis ? Atherosclerosis: Word bank: fat exercise pressure smoking Factor Alcohol Drugs Smoking Exercise Diagram Process Risk factors Normal Veins or Arteries Atherosclerosis Heart attack Alcohol S________ Drugs No exercise All these risk Healthy arteries allow red Fatty deposits block veins The heart starved of Notes factors contribute blood cells to flow freely and arteries reducing oxygen suffers a heart to heart disease. through the heart tissue. blood flow. attack.

Slide 21: Science Interactive LTD Copyright 2005 Understanding heart attacks During a heart attack, the arteries supplying the heart and its muscular ventricles become blocked with f______ deposits that have become detached from the lining of the coronary arteries. Any heart muscle ‘downstream’ of the blockage is starved of o_______ and dies. The heart can withstand losing about 50% of its muscle function. A fatal heart attack is where the blockage deprives over 50% of heart muscle of their essential oxygen and nutrients. What ‘lifestyle factors’ increase the risk of a heart attack ? Heart attack: Word bank: fatty oxygen Blocked arteries Heart attack Heart bypass Mechanical heart Diagram A high fat diet may During a heart attack, If your coronary arteries A final option, if the heart Notes lead to fatty deposits the muscle tissue is become blocked, you becomes damaged beyond blocking your arteries. starved of oxygen and can opt for a triple repair, is to have a These can break free nutrients because of a bypass, where veins mechanical heart. Post causing a blockage in blockage in the from your leg replace operative survival rates the arteries supplying coronary arteries. The the blocked arteries for this procedure are the heart. muscle tissue then dies. supplying the heart. relatively low.

Slide 22: Science Interactive LTD Copyright 2005 Sickle cell anaemia Sickle cell anaemia is a genetic disease of the blood that affects African populations. The disease is passed through faulty genes carried by the paternal s_____ or maternal eggs. In humans who have the disease, red blood cells are sickle shaped with a reduced s_________ area, which reduces the amount of o________ carried to the cells and tissues. This disease is normally fatal. How can genetic counselling help parents and families who carry the faulty gene for sickle cell anaemia make choices when having children ? Sickle cell anaemia: Word bank: sperm surface oxygen Normal blood Sickle cell Oxygen transport Diagram Normal cell Sickle cell O2 O2 O2 O2 O2 O2 O2 O2 O2 O2 O2 O2 O O2 O2 O2 2 Oxygen Oxygen Oxygen Oxygen Normal red blood cells Faulty genes inherited Less oxygen than normal reaches Notes have no nucleus and are from one or both parents the tissues and cells. The sickle biconcave in shape to help cause sickle cell disease. shaped red blood cells are not able transport oxygen around The surface area of the to carry sufficient oxygen because the body. sickle cell is reduced. of their reduced surface area.

Slide 23: Science Interactive LTD Copyright 2005 Disease causing microbes Bacteria, v_________ and fungi are all microbes which are able to cause disease in humans. Not all diseases are caused by microbes, for example heart disease is caused by a number of lifestyle factors like a high fat diet, smoking or excessive a________ intake. Microbes can be found anywhere, in the air, the soil, on food, or on unclean surfaces and in water. A particular risk of infection is associated with sharing unclean needles. Blood born viruses like HIV and hepatitis can be passed on from person to person. Why are intravenous drug users who inject drugs like heroin or crack at particular risk at contracting viruses like HIV and hepatitis? Microbes: Word bank: viruses alcohol Bacteria Viruses Fungi Needles Diagram A bacteria is a single Viruses are extremely Some types of fungi can Blood borne viruses Notes celled organism. All the small. Viruses are not cause disease or including and HIV bacteria in the world whole cells. Their infections in humans. hepatitis can be passed weigh more than any genes are found in a Athlete’s foot is caused from person to person by other class of species. protective protein coat. by a fungi. They needle sharing. Drug They are the most They reproduce inside reproduce by producing users have a high risk of successful species. other cells. spores. contracting HIV.

Slide 24: Science Interactive LTD Copyright 2005 Transmission of bacterial disease one Bacteria can be found in every living o_________, on every surface and even in the air we breathe. Some bacteria are very useful, whilst other cause diseases like cholera and dysentery. There are a number of ways in which bacteria can enter your body. By understanding how disease enters our body, we can reduce our risk of contracting or spreading the disease. Explain why most infections caused by bacteria are entirely avoidable in humans ? Bacterial infecting people: Word bank: organism Food Touching Sewage Surfaces Diagram Fresh food and drink Touching an infected Water containing human Surfaces in kitchens and Notes can be infected with person can lead to the waste is full of bacteria. bathrooms can be home bacteria. Some foods transmission of the Before water is fit to to many thousands of contain bacteria that disease causing bacteria. drink it is filtered, unwanted and harmful can only be destroyed Bacterial infections cleaned and sterilised bacteria. Always keep by cooking. How does causing nausea can be using chlorine which is these surfaces clean by this destroy bacteria ? spread by touch. antiseptic. using disinfectants.

Slide 25: Science Interactive LTD Copyright 2005 Transmission of bacterial disease two Bacteria has to enter our bodies before they can cause d________. They can enter via the digestive system, the nose or cuts in our s____. Our lifestyles determine our risk to infection. In refugee camps, where there is little or no treatment of sewage, poor nutrition and many people living in unsanitary conditions, disease spreads rapidly killing many people. We all have a personal responsibility for how we live and how clean we are. Explain how modern intensive farming can lead to the transmission of viruses like ‘bird flu’ or ‘mad cows disease: BSE’ in humans ? Bacteria infecting people: Word bank: bacteria skin Animals Washing hands Sneezing Waste Diagram Animals are a potential Washing your hands Using a tissue and Human waste is another Notes source of infection. before meals or after covering your nose source of bacterial Most farm raised going to the toilet prevents you from infection. Decaying fruit, animals are given huge reduces the risk of infecting other people. meat and vegetables play amounts of antibiotics infection from bacteria Millions of microbes are host to many different to control their levels found in human waste expelled from your nose bacterial colonies. Why of disease and bacteria. like faeces. every time you sneeze. do we treat our waste ?

Slide 26: Science Interactive LTD Copyright 2005 Human immunity You can have two types of immunity: Innate and acquired immunity. Innate immunity is your body’s response to an i_________. When you are infected by a microbe, your white blood cells will respond by engulfing the microbes and produce the right sort of antibodies. Acquired immunity can come from vaccinations, breast feeding or booster jabs. During breast feeding, your mother’s milk contains a__________ which can help you fight any disease until your own immune system develops. Can you remember any of the vaccinations that you have been given ? Types of immunity: Word bank: infection antibodies Innate immunity Vaccination Breast feeding Boosters Diagram Plasma Red Blood Cells Neutrophils Blood Lymphocytes Cells Notes White blood cells find and destroy We can acquire immunity in three ways: During vaccination, microbes, reducing our risk of vaccines are given to us when we are young to protect us against dying from infection. Although less diseases like smallpox. Breast feeding allows the newborn to have all numerous than red blood cells, there the same antibodies as their mothers. Boosters are given when there are an essential part of our immune is an outbreak of a disease or to the young and old. These are given system. by injection.

Slide 27: Science Interactive LTD Copyright 2005 Blood fighting infection one Blood also contains white blood cells, platelets and antibodies that are all part of the immune system which is responsible for fighting disease. White blood cells are a collection of cells that help recognise, fight and destroy foreign material like b________ and viruses. Lymphocytes produce antibodies which help clump bacteria together so they can be engulfed by neutrophils (also called phagocytes) When a new m_________ enters the body, new antibodies are made which recognise only that microbe. After the microbe has been destroyed, these antibodies remain in the blood, giving you immunity to that microbe. Why do babies have the same immunity as their mothers ? Immune response in blood: Word bank: bacteria microbe Stage one Stage two Stage three Stage four Diagram Microbes enter your Microbes use the blood Antibodies produced by Phagocytes or Notes body from sources like and other tissues to lymphocytes in response neutrophils begin to unclean hands or food begin to multiply. They to a specific microbe are search, and destroy that has not been have a ready source of able to recognise and microbial cells. They cooked or handled oxygen and nutrients. If clump together these release enzymes which properly. Describe the microbes continue to invaders. It takes about 2 rip open and destroy the four other ways of multiply, the toxin they – 5 days for lymphocytes microbes. They also microbial transmission produce would kill you. to make these antibodies. neutralise any microbial

Slide 28: Science Interactive LTD Copyright 2005 Blood fighting infection two The skin is the largest o______ in the body. One of its main functions is to act as a ‘physical barrier’ to the entry of microbes. If cut, you are at risk of infection caused by the entry and subsequent multiplication of microbes in the circulatory system. Once cut, the skin rapidly heals to prevent further blood loss and the entry of microbes into the b______ stream. Healing and scab formation is helped by the clotting response. This is where platelets and fibrinogen, both carried in the blood, form a tightly knitted scab that closes the wound. What role do plasters play in helping us avoid infection from microbes ? Forming a scab: Word bank: organ blood Human skin Stage one Stage two Stage three Diagram A key role of the skin is to help Notes When you cut healthy skin, a three stage response occurs before maintain core body temperature scab formation takes place. One: The skin is cut, bleeding at 37oC. The skin also has many occurs. Two: Platelets are pumped to the injury site. Three: other roles. It protects your body Platelets and fibrinogen form a scab which prevents further against disease and bacterial bleeding and closes the wound. White blood cells are also infection by acting as a physical rushed to the injury site to destroy what ? barrier

Slide 29: Science Interactive LTD Copyright 2005 Blood fighting infection three White blood cells (neutrophils) constantly roam around the circulatory system. Unlike red blood cells, they do not carry o_______, but form part of your immune system. Neutrophils are able to find, attach and engulf m_______. When the invading microbes are fully engulfed, they are digested and destroyed by enzymes inside the cell. These white blood cells are also able to neutralise any microbial toxins, therefore preventing these toxins from poisoning your body. HIV affects your white blood cell count...how does this leave you vulnerable to other diseases ? Neutrophils engulfing bacteria: Word bank: oxygen microbes Components of the blood Neutrophils (Phagocytes) in action Diagram Plasma Red Blood Cells Neutrophils Blood Lymphocytes Cells An essential role of blood is to fight disease. Images of a neutrophil (phagocyte) in action. They Notes Lymphocyte antibodies and neutrophils search and have long thread like features which literally trap the destroy microbes. Without an immune system we bacteria and draw them in to be engulfed by the couldn't survive in our environment. neutrophil. HIV destroys these cells !

Slide 30: Science Interactive LTD Copyright 2005 Blood fighting infection four Despite millions of neutrophils, which search and destroy microbes that enter the bloodstream, some microbes are difficult to find and evade detection by these immune cells. The other white blood cells, lymphocytes produce a__________ which are specific to an individual microbe. They work by binding onto the surface of the microbe and clumping them together. This makes their detection by neutrophils easier. Your body also remembers this microbe and continue to produce antibodies for the rest of your life, ready for the next time. Why do they say that you never catch the same cold twice ? Antibodies in your blood: Word bank: antibodies Bacterial infection Producing antibodies How antibodies work Diagram Bacteria enter and multiply in Several days after infection, Antibodies are able to clump Notes the blood. They spread out and your lymphocytes start to together microbes in the blood try to avoid detection by your produce large numbers of by binding themselves to the neutrophils. What happens if antibodies which roam around their surface. This aids their they are left to continue to the bloodstream looking for detection by neutrophils which multiply in the bloodstream ? invading microbes. then destroy them.

Slide 31: Science Interactive LTD Copyright 2005 Microbes and your health When microbes like viruses or bacteria enter your body, you develop s_________ alongside the disease. These symptoms are a result of either toxins produced by rapidly multiplying bacteria or viruses destroying your cells found in organs like your lung. Your body temperature rises, you may feel generally unwell, sleepy and experience a____ or pains. During the illness period, your body begins to make new antibodies and neutrophils to search and destroy the microbes. Look at the graph and see how you body responds to illness or disease caused by microbes. Microbes and your health: Word bank: symptoms aches Notes incubation illness recovery Measurements of body temperature, microbes and antibody levels were taken Antibodie s during a 14 days period. 1: How long would you have felt ill during the 14 days ? 2: How many days did the Microbe microbe replicate itself in the body before your immune system kicked in ? 3: Why did the number of microbes start to decrease after Body temp 5 days ? normal 4: Explain why the level of 37o C antibodies in your blood remain 6 time days 8 0 2 4 10 12 14 high, even during recovery ?

Slide 32: Science Interactive LTD Copyright 2005 Extension questions and homework 1. Define the following terms: Blood, Immunity, Microbe, Bacteria, Virus, Fungi, Immunity, Antibodies & Vaccine. 2. Look at the diagram of the three types of microbes. Complete the table. Microbe Examples How are they spread What symptoms do they produce Bacteria Viruses Fungi 12. Name three cells types contained in the blood and give a function for each. What’s the role of the clear plasma fluid found also in blood. 13. Using the diagram of the circulatory system answer the following questions: (a) Which blood vessels carry blood away from the heart. (b) Which blood vessels carry blood to the heart. (c) Name the blood vessel through which blood enters the heart from the body (d) Describe the path blood takes from the lung surface to the liver. 14. Complete the following table: Arteries Capillaries Veins Carries blood ___ the heart. Connects arteries and _______. Carries blood to the heart. Has a ______ wall carrying Has a _____ wall and carries blood Has a _____ wall carrying blood at blood at ______ pressure. The at _____ pressure to allow gas ______ pressure. Contains valves to aorta is the biggest example. exchange. stop back flow.

Slide 33: Science Interactive LTD Copyright 2005 6: Look at the information in the table below. It shows the patient’s temperature when suffering from a bacterial infection: Day 0 2 4 6 8 10 12 14 16 18 Body temperature 37oC 37oC 38oC 39oC 39oC 40oC 40oC 38oC 37oC 37oC a) What symptom of the disease is shown by the data. b) How long was the incubation period. c) What caused the fever and how long did it last. 7: a) What is an antibiotic and how was the first antibiotic discovered. b) In hospitals, patients are treated for bacterial infection by doctors using antibiotics. Some of

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