The Cardiovascular System

1. The Cardiovascular System

2. The Cardiovascular System

3. At one time people believed their emotions came from their hearts because the heart beats faster when a person is scared or excited. • We now know that emotions come from the brain and that the brain controls the heart.

4. The circulatory system is the transport system of the body and has four major functions: • To transportoxygen and carbon dioxide around the body • To distributenutrients and transport waste • To maintainbodytemperature • To circulatehormones

5. Our circulatory system is a “complete, double” system incomplete, double complete, double complete, single De-oxygenated blood Mixed blood Oxygenated blood

6. Major components of the Circulatory System • STRUCTURE and FUNCTION • The circulatory system is made up of 3 components: • The heart (a pump) – that pushes blood through the vessels • Blood vessels • A fluid in which materials are transported (i.e. blood) heart blood vessels blood

7. Major components of the Circulatory System heart blood vessels blood

8. Major components of the Circulatory System heart blood vessels blood - There are 96,000 km of blood vessels in your body that are responsible for delivering the required materials to 100 trillion cells. - No body cell is farther than 2 cells away from a blood vessel that can deliver what that cell needs to survive through diffusion & osmosis. - The heart beats, on average, 72x per minute from the beginning of life until death.

9. Organization of the Circulatory System The circulatory system is broken down into 2 main circuits: systemic pulmonary a) The Pulmonary circuit – blood vessels that carry blood to the lungs where it picks up oxygen and then back to the heart. b) The Systemic circuit – blood vessels that carry oxygen rich blood to the body tissues and deoxygenated blood back to the heart. systemic

10. The Heart – page 139-140 1. The heart is really a double pump separated in the middle by a wall called a septum. • The heart consists of 4 chambers. The chambers closer to the top of each side are called atriums, the chambers closer to the bottom are called ventricles. 4. The right side of the heart receives deoxygenated blood back from the body and pumps it to the lungs to pick up more oxygen. 3. The left side of the heart receives oxygen-rich blood from the lungs and pumps it to the body. neck and head Vena cava left lung right lung Pump O2-rich blood to the body Receives CO2-rich blood from the body Vena cava septum trunk and legs

11. Blood vessels – page 140 Vein Artery blood exchange in the capillaries Arteriole Venule Capillary Blood from heart blood going to heart O2 CO2

12. Blood vessels – page 140 • Arteries: blood vessels that carry blood away from the heart. •  thick walls of muscular layers •  largest= aorta, leads directly from the left ventricle into arteries around the body.

13. Veins: blood vessels that carry blood towards the heart.  veins have thin walls (compared to arteries) and contain valves to prevent back flow of blood (i.e. so blood can be pumped against gravity).  major veins= vena cavasthat carry deoxygenated blood directly to the right atrium of the heart. c) Capillaries: very small blood vessels, red blood cells must travel single-file, gases exchange across the walls of capillaries and into the surrounding tissues.

14. Let’s take a closer look at the heart A blood cell travels from …. superior vena cava A aorta K right pulmonary artery E left pulmonary artery F right pulmonary vein G left pulmonary vein H I left atrium right atrium C J left ventricle D right ventricle B inferior vena cava

15. Let’s take a closer look at the heart A blood cell travels from …. aorta superior vena cava right pulmonary vein left pulmonary artery right pulmonary artery left pulmonary vein left atrium right atrium left ventricle right ventricle inferior vena cava

16. Let’s take a closer look at the heart – A blood cell travels from …. aorta superior vena cava right pulmonary artery left pulmonary artery right pulmonary vein left pulmonary vein left atrium right atrium left ventricle right ventricle inferior vena cava

17. Let’s take a closer look at the heart A blood cell travels from …. aorta superior vena cava right pulmonary artery left pulmonary artery right pulmonary vein left pulmonary vein left atrium right atrium left ventricle right ventricle inferior vena cava

18. Let’s take a closer look at the heart – page 138 A blood cell travels from …. aorta superior vena cava right pulmonary artery left pulmonary artery right pulmonary vein left pulmonary vein left atrium right atrium left ventricle right ventricle inferior vena cava

19. 5. Blood pressure: your pulse is what you feel as a surge of blood passes through your arteriesThe surge of blood stretches the artery open, causing a pressureThe pressure of blood, as it is pumped out of the left ventricle into the artery is called Systolic pressureWhen there is no surge of blood pumped into the artery, the artery is in a state of relaxation because it is not being stretched openThe pressure in the artery walls in this state of relaxation is called Diastolic pressure.