Cardiovascular system
- 1. © Boardworks Ltd 20041 of 49 Circulation and Respiration The Cardiovascular System
- 2. © Boardworks Ltd 20042 of 49 Two Types of Circulation The Cardiovascular System The cardiovascular system Structure of the heart Blood Vessels Cardiovascular Problems Contents Summary quiz
- 3. © Boardworks Ltd 20043 of 49 How do substances move around the body? Read pg. 546, -Your cardiovascular system- and summarize the functions and the parts of the cardiovascular system.
- 4. © Boardworks Ltd 20044 of 49 The Cardiovascular System
- 5. © Boardworks Ltd 20045 of 49 The Cardiovascular System The Heart Create the pressure necessary to move the blood Blood Fluid that delivers nutrients and oxygen to the cells Blood Vessels Transports blood throughout the human body.
- 6. © Boardworks Ltd 20046 of 49 The Cardiovascular System • amino acids • glucose Maintain Homeostasis Carry Nutrients Remove Wastes Chemical Signals Regulates Temperature • CO2 • Urea • Insulin • Estrogen • Testosterone • Melatonine
- 7. © Boardworks Ltd 20047 of 49 Two Types of Circulation The Cardiovascular System The cardiovascular system Structure of the heart Blood Vessels Cardiovascular Problems Contents Summary quiz
- 8. © Boardworks Ltd 20048 of 49 The structure of the heart – exterior The heart pumps blood around the circulatory system. What is the heart made of? The heart is made of muscle and keeps pumping blood around your body, even when you are asleep! muscle tissue What do the blood vessels on the outside of the heart do? blood vessels supply blood to muscle tissue
- 9. © Boardworks Ltd 20049 of 49 Inside the heart The inside of the heart is divided into two sections so that the two types of blood (oxygen-rich and oxygen-poor) are kept apart. oxygen-poor blood right side of the heart oxygen-rich blood left side of the heart Remember that the heart is always labelled as if it is in a body facing you, so the right side of the heart is on the left of the diagram.
- 10. © Boardworks Ltd 200410 of 49 Inside the heart right side of the heart left side of the heart
- 11. © Boardworks Ltd 200411 of 49 The arrangement of the circulatory system means that these two types of blood do not mix. Why is this important? Two types of blood The circulatory system carries two types of blood: oxygen-rich blood c oxygen-poor blood blood travelling to the body cells high oxygen content low carbon dioxide content blood travelling away from the body cells low oxygen content high carbon dioxide content
- 12. © Boardworks Ltd 200412 of 49 The structure of the heart – interior The inside of the heart is divided into two sections to keep oxygen-rich and oxygen-poor blood separate. Each side of the heart is also divided into two sections. Each section of the heart is called a chamber. How many chambers are there? right side of the heart left side of the heart 4
- 13. © Boardworks Ltd 200413 of 49 The chambers of the heart The four chambers of the heart have special names: A lower chamber is called a ventricle. An upper chamber is called an atrium (plural atria). right ventricle right atrium left ventricle left atrium
- 14. © Boardworks Ltd 200414 of 49 What do atria and ventricles do? The chambers of the heart have different functions. The atria collect blood that enters the heart. The ventricles pump blood out of the heart. blood to the body blood from the body blood to the lungs blood from the lungs
- 15. © Boardworks Ltd 200415 of 49 Preventing backflow Blood always flows in the same direction as it moves through the heart during each circulation of the body. Why is it important that blood does not flow backwards?
- 16. © Boardworks Ltd 200416 of 49 The chambers of the heart are separated by valves which prevent blood from flowing in the wrong direction. Heart valves There are valves between the atria and the ventricles… …and there are valves leading out of the ventricles. valve between right atrium and right ventricle valve between left atrium and left ventricle valve leading out of right ventricle valve leading out of left ventricle
- 17. © Boardworks Ltd 200417 of 49 How are valves held in place? The valves between the atria and ventricles are connected to the inner walls of the heart by tough tendons. valve open
- 18. © Boardworks Ltd 200418 of 49 How are valves held in place? The tendons allow the valves to close and hold the valve flaps in place. They prevent the valves from flipping up and turning inside out. Why is this important? valve open valve closed
- 19. © Boardworks Ltd 200419 of 49 How do valves work? A valve acts like a door that only opens in one direction. If the door is held by someone at a fixed point, only the arm moves as the door opens and closes. When the door is closed the arm is fully extended, so the door can only be opened in one direction.
- 20. © Boardworks Ltd 200420 of 49 How do valves work? A valve acts like a door that only opens in one direction. In the heart, the tendons holding the valve are like the arm holding the door. One end of each tendon is fixed to the wall of the heart and so the valve can only open in one direction.
- 21. © Boardworks Ltd 200421 of 49 Two Types of Circulation The Cardiovascular System The cardiovascular system Structure of the heart Blood Vessels Cardiovascular Problems Contents Summary quiz
- 22. © Boardworks Ltd 200422 of 49 Blood travels throughout the body in hollow tubes called blood vessels. There are three types: Blood Vessels ARTERIES Carry blood away from the heart. Thick and highly elastic walls with a layer of smooth muscle. Expansion/contraction of artery walls provides additional pumping. When you measure your pulse, what you feel is the rhythmic expansion and contraction of an artery as blood moves through it. CAPILLARIES A network of capillaries joins the arteries with all the body. One-cell-thick Is where gases, nutrients, and other materials are transferred from blood to cells vice versa. No cell in the body is more than three or four cells away from a capillary VEINS Carry blood toward the heart Thinner walls than arteries & larger inner circumference. Not elastic, and they cannot contract (need contraction of muscles). Have one-way valves that prevent the blood from flowing backward.
- 23. © Boardworks Ltd 200423 of 49 Blood travels throughout the body in hollow tubes called blood vessels. There are three types: Blood Vessels
- 24. © Boardworks Ltd 200424 of 49 Blood Vessels
- 25. © Boardworks Ltd 200425 of 49 Two Types of Circulation The Cardiovascular System The cardiovascular system Structure of the heart Blood Vessels Cardiovascular Problems Contents Summary quiz
- 26. © Boardworks Ltd 200426 of 49 How does blood circulate around the body? The left side of the heart pumps oxygen-rich blood to the rest of the body. This blood supplies the body’s cells with oxygen. What gas does the blood then pick up from the body’s cells and where does the blood go next? body’s cells body’s cells
- 27. © Boardworks Ltd 200427 of 49 The oxygen-poor blood needs to lose the carbon dioxide and pick up more oxygen. How does it do this? How does blood circulate around the body? Blood picks up carbon dioxide from the body’s cells. This oxygen-poor blood then travels back to the right side of the heart. body’s cells body’s cells
- 28. © Boardworks Ltd 200428 of 49 lungslungs Where does this oxygen-rich blood then travel to? How does blood circulate around the body? Next, the right side of the heart pumps oxygen-poor blood to the lungs. In the lungs the blood gets rid of the waste carbon dioxide and collects more oxygen. body’s cells body’s cells
- 29. © Boardworks Ltd 200429 of 49 The oxygen-rich blood then returns to the left side of the heart. This completes the blood’s journey around the body. Why is the journey of blood through the circulatory system called a double circulation? How does blood circulate around the body? body’s cells body’s cells lungslungs
- 30. © Boardworks Ltd 200430 of 49 During one complete circuit of the body, blood passes through the heart twice. The heart has two jobs to do and so the circulatory system involves a double circulation. What are the two jobs that the heart carries out during this double circulation? A double circulatory system body’s cells body’s cells lungslungs
- 31. © Boardworks Ltd 200431 of 49 The Heart and Circulatory System The circulatory system Structure of the heart How the heart pumps blood Valves in the heart Summary quiz Contents Summary quiz
- 32. © Boardworks Ltd 200432 of 49 How does the heart pump blood? All the parts of the heart on either side, work together in a repeated sequence. The two atria contract and relax; then the two ventricles contract and relax. This is how blood moves through the heart and is pumped to the lungs and the body. One complete sequence of contraction and relaxation is called a heartbeat.
- 33. © Boardworks Ltd 200433 of 49 Heartbeat animation
- 34. © Boardworks Ltd 200434 of 49 What does a doctor hear when they listen to a patients’ heart? Listening to a beating heart: lub-dub The “lub” is caused by the closing of the valves leading to the ventricles. The “dub” is caused by the closing of the valves leading out of the heart. lub-dub, The sound of a heartbeat is the sound of the heart valves. lub-dub, lub-dub, lub-dub, lub-dub, lub-dub…
- 35. © Boardworks Ltd 200435 of 49 Measuring a beating heart You can measure how fast your heart is beating by taking your pulse. Each pulse that you feel is due to the pressure of blood leaving the heart as the left ventricle contracts. Place the fingertips of one hand on the opposite wrist, where an artery passes near the surface of the skin. What is your heart rate, in beats per minute, right now?
- 36. © Boardworks Ltd 200436 of 49 …in one hour? …in one day? …in one year? …in 70 years? How many heartbeats? If your heart beats at an average rate of 70 times per minute, how many heartbeats are there… 70 x 60 = 4,200 x 24 = 100,800 x 365 = 36,792,000 x 70 = 100,800 36,792,000 2,575,440,000 4,200
- 37. © Boardworks Ltd 200437 of 49 Two Types of Circulation The Cardiovascular System The cardiovascular system Structure of the heart Blood Vessels Cardiovascular Problems Contents Summary quiz
- 38. © Boardworks Ltd 200438 of 49 The two sides of the heart
- 39. © Boardworks Ltd 200439 of 49 Inside the heart – labelling activity
- 40. © Boardworks Ltd 200440 of 49 Inside the heart – labels
- 41. © Boardworks Ltd 200441 of 49 Chambers of the heart – activity
- 42. © Boardworks Ltd 200442 of 49 The sequence of a heartbeat
- 43. © Boardworks Ltd 200443 of 49 Journey of blood around the body
- 44. © Boardworks Ltd 200444 of 49 Multiple-choice quiz