Life sciences Grade 10 CAPS: structured, clear, practical Helping teachers unlock the power of NCS KNOWLEDGE AREA: Life processes in plants and animals Topic 9: Transport systems in mammals, humans Circulatory system

CAPS SPECIFIC AIMS 1. Knowing Life Sciences 2. Investigating Phenomena in Life Sciences 3. Appreciating and Understanding the History, Importance and Applications of Life Sciences in Society

Specific Skills Access information Select key ideas Recall information Describe knowledge of NS Build a conceptual framework Organise or reorganise knowledge Write summaries Develop flow charts and mind maps Recognise patterns and trends Apply knowledge in new contexts Use knowledge in a new way Analyse information/data Critically evaluate scientific information Recognise relationships between existing knowledge and new ideas Identify assumptions Categorise information

CIRCULATORY System The blood circulatory system is made up of the: 1. The heart 2. The blood vessels

Terminology Deoxygenated Oxygenated 10. Vertical septum Bicuspid valve Tricuspid valve Aorta Pulmonary vein Pulmonary artery Superior vena cava Inferior vena cava 10. Vertical septum 11. Semi lunar valves 12. Lymph 13. Tissue fluid 14. Double circulation 15. Pulmonary circuit 16. Systemic circuit Note to the teacher: This list can be used as a pre learning tool, were you can ask learners to copy them down and find their meanings before you begin the module. It is also can be used as homework at the end of every sub section. Learners can be asked to define a few of these terms at the end of every sub section. The definitions appear on the last slide.

Solution 8. The vein that carries deoxygenated blood from the upper parts of the body to the right atrium of the heart. 9. Vein that carries deoxygenated blood from the lower parts of the body to the right atrium of the heart. 10. Tissue that separates the heart into right and left halves. 11. Valves found at the entrance of blood vessels to prevent the backflow of blood. 12. Tissue fluid that enters the lymph vessels 13. Circuit of blood that flows from the heart to the lungs and back to the heart 14. Circuit of blood from the heart to all parts of the body and back to the heart. 1. Blood which has more carbon dioxide than oxygen. 2. Blood that has more oxygen than carbon dioxide. 3. Valve that is found between left atrium and ventricle 4. Valve that is found between right ventricle and atrium. 5. Large artery that carries oxygen blood out of the heart to all parts of the body. 6. Artery that carries deoxygenated blood from heart to the lungs 7. Vein that carries oxygenated blood from the lungs to the heart

The Human Heart Location: The heart is found in the middle of the chest (thoracic) cavity within the ribcage. It lies behind the sternum and is situated more tothe left. Note to the teacher: Use your torso or a transparency or even a skeleton to pin point the exact location of the heart. You can find find suitable pictures on line and use with your iBox. Also point out to learners how the location assists in protection. The highlighted words are the key words that are used to describe the location. Point this out to learners telling them that these are the words they need to remember for the location of the heart.

External Structure of the Heart . The heart is enclosed within a double walled sac called the pericardium. There are a large number of blood vessels that enter and leave the heart. The superior and inferior vena cava and the pulmonary veins enter the heart. The aorta and the pulmonary arteries leave the heart. The coronary arteries and veins supply and drain the heart muscle itself. Note to the teacher: Use the diagram alongside to enhance your discussion. Point out the various blood vessels . Bring the shape of the aorta to the attention of the learners. Remember this shape can be used to identify the aorta. It is a distinguishing feature point this out to the learners it will help them to easily indentify the aorta. A quick assessment opportunity here is to provide them with a diagram and ask the to lable and provide a caption. Such a question would carry 11 marks you should give them 11 minutes. Timed activities like this are important as it will help the learners with their time management, remember in life sciences it is 1 mark per minutes.

Internal Structure of the Heart The heart is separated into right and left halves by the vertical septum. Each half is further divided into an upper- the atrium/atria and lower portions, the ventricles. There is a right and left atrium and a right and left ventricle. The atria and ventricles are separated from each other by valves. The bicuspid or mitral valve (with 2 cusps) separates the left atrium from the left ventricle. The bicuspid valve prevents the blood from flowing back into left atrium when the ventricle contracts. Note to the teacher: The best way to discuss the structure of the heart is to start with an outline of the heart and add on the different valves and blood vessels as you discuss them. In this way the child can easily follow the structure and it is built up rather than the full scale diagram that appears in the next slide. This diagram can be overwhelming to the child but it must be discussed with them. It is also a good idea to expose them to a number of different diagrams to help able to identify and label any diagram that might be given to them.

The right atrium is separated from the right ventricle by the tricuspid valve. The tricuspid valve has 3 cusps. The tricuspid valve prevents the blood from flowing back into the right atrium when the right ventricle contracts. Walls of the atria are much thinner than the walls of the ventricles. This is because the atria pump blood only to the ventricles while the ventricles pump blood much further. Thickness of the walls of the heart is associated with the distance the blood is pumped. The thickness of the wall determines the amount of pressure that is created in the blood. Note to the Teacher: Remember to use the diagram alongside with your discussion. Remember visual is very important. Remember to time the question after 2 minutes discuss the answer which appears on the next slide.

Blood vessels that enter and leave the heart. Deoxygenated blood refers to blood that has more carbon dioxide than oxygen. Oxygenated blood is blood that has more oxygen than carbon dioxide. Note to the teacher: Remember to emphasis that both the blood types have the both gases but just in different amounts

Blood vessels that enter and leave the heart. Veins bring blood to the heart . Arteries carry blood away from the heart. The superior vena cava carries deoxygenated blood from the upper parts of the body to the right atrium. The inferior vena cava carries Deoxygenated blood from the lower half the body to the right atrium. The pulmonary artery carries deoxygenated blood from the right ventricle to the lungs.

The pulmonary veins carry oxygenated blood from the lungs to the left atrium. The aorta carries oxygenated blood from the left ventricle to all parts of the body. The coronary artery is a branch of the aorta and carry food and oxygen to the heart muscle. The coronary veins carry the metabolic waste and deoxygenated blood away from the heart muscle.

Something for you to do Copy this table showing the different blood vessels found in the heart and complete it. Name of blood vessel Type of blood carried Where the blood comes from? Where the blood vessel goes to? Pulmonary vein lungs enters left atrium of heart deoxygenated Right ventricle the lungs Superior vena cava lower parts of body right atrium Aorta Note to the teacher: This is a good learning tool. Please ensure that learners have copied it and completed it, provide them with the answers

Solution Table showing the different blood vessels found in the heart. Name of blood vessel Type of blood carried Where does the blood come from? Where does the blood go to? Pulmonary vein oxygenated lungs The left atrium of the heart Pulmonary artery deoxygenated Right ventricle The lungs Superior vena cava The upper parts of the body The right atrium of the heart Inferior vena cava The lower parts of the body Aorta Left ventricle of the heart All parts of the body

The Cardiac Cycle A healthy heart beats about 70 times per minute. A single heart beat is also called a cardiac cycle. A complete heart beat lasts about 0.8 seconds. Each cardiac cycle is controlled by the SA node. The SA node is a natural pacemaker, it is found in the right atrium. A single heart beat or cardiac cycle is made up of 3 phases. These 3 phases are: Atrial systole: which occurs in about 0.1 seconds. Ventricular systole: which occurs in about 0.3 seconds. Diastole: which occurs in about 0.4 seconds. Systole refers to a contraction of the heart muscle. Diastole refers to a relaxation of the heart muscle.