1. The Cardiovascular System

2. Tasks of the CV System Carry oxygen from the lungs to body cells.
Carrying carbon dioxide, a waste gas, from your cells back to the lungs to be exhaled.
Delivering other waste products to the kidneys for removal from the body.

3. Tasks of the CV System
Absorbing nutrients from food and delivering nutrients to body cells.
Helping white blood cells fight disease by attacking infectious organisms (pathogens).

4. The Heart
The heart is the muscle that makes the cardiovascular system work.
It consists of a special type of muscle called myocardium.
It is composed of 4 chambers:
The 2 upper chambers are the atria
The 2 lower chambers are the ventricles

5. The Heart
A wall of tissue called the septum separates the 4 chambers of the heart.
One way valves at the exits of each heart chamber guarantee that blood can flow in only one direction.

6. The Heart
A small area of the right atrium serves as a natural pacemaker, controlling the rate at which the heart beats.
Electrical impulses stimulate the atria to contract, forcing blood into the ventricles.
These electrical impulses travel through the heart to an area between the 2 ventricles.
There they stimulate the muscles of the ventricles to contract, pumping blood out of the heart

7. Blood
Blood is the fluid that delivers oxygen, hormones, and nutrients to the body cells and carries away waste that the cells produce.
Blood is produced in the bone marrow of long bones.

8. Blood
Plasma
The fluid in which other parts of the blood are suspended.
It makes up 55% of the total blood volume.
It’s mainly water (92%), but also contains nutrients, proteins, salts, and hormones.

9. Blood
Red Blood Cells
The cells that transport oxygen and carbon dioxide molecules.
Makes up about 40% of normal blood
Each red blood cell contains hemoglobin, a protein in the blood which:
Contains iron that binds with oxygen and carbon dioxide molecules
Gives the blood it’s red color

10. Blood White Blood Cells
The cells that protect the body against infection.
Some white blood cells:
Surround and ingest the organisms which cause disease.
Form antibodies that provide immunity against a second attack from a specific disease
Fight allergic reactions

11. Blood Platelets The cells in the blood that cause blood clots to form.
When the wall of a blood vessel tears, they collect at the tear and release a chemical which causes the blood to produce small fibers (fibrin) which trap the platelets along with red and white blood cells.
The mass of fibrin, platelets, and red and white blood cells plug the injury and forms a clot which dries to form a scab.

12. Blood Vessels
Blood is distributed throughout the body through a network of vessels.
There are more than 60,000 miles of blood vessels in your body.
The blood vessels are divided into:
Arteries
Capillaries
Veins

13. Blood Vessels
Arteries
Blood vessels that carry oxygenated blood away from the heart.
They branch into progressively smaller vessels called arterioles which deliver blood to the capillaries.
The arteries thick walls enable it to withstand the high blood pressure it is subjected to every time the heart beats.

14. Blood Vessels The artery walls are composed of three layers
A tough, fibrous outer layer
A thick muscular middle layer
An inner layer of smooth epithelial cells

15. Blood Vessels
The muscular wall of the artery helps the heart pump the blood by contracting when the heart relaxes.
Since it keeps pace with the heart, we can measure heart rate by counting the contractions of the artery (pulse)

16. Blood Vessels Capillaries
The small blood vessels that carry blood from the arterioles to the venules which empty into veins.
Some capillaries are 50 times thinner than a strand of hair.

17. Blood Vessels
It is through the thin capillary walls that oxygen and nutrients pass from the blood to body cells, and waste products move from cells into the blood.

18. Blood Vessels
Capillaries near the skin’s surface dilate (open) or constrict (close) to help regulate the body’s temperature.

19. Blood Vessels
Veins
The blood vessels that return deoxygenated blood to the heart.
The walls of the veins are thinner than those of the arteries, so blood is visible through the skin on some parts of your body.
The blood appears blue because your skin refracts light.

20. Blood Vessels
Many veins have valves, that along with muscle contractions from surrounding muscles, help prevent the backflow of blood as it’s pumped back to the heart.

21. Circulation of Blood Pulmonary Circulation
The movement of blood from the heart, to the lungs, and back to the heart again.
Deoxygenated blood enters the right atrium through the vena cava.
The right atrium contracts, pushing the blood into the right ventricle.
The right ventricle contracts, pushing the blood into the pulmonary artery.
The pulmonary artery takes the blood to the lung

22. Circulation of Blood
In the lung, deoxygenated blood is exchanged for oxygenated blood
The pulmonary vein takes the oxygenated blood to the left atrium.
The left atrium contracts, pushing the blood into the left ventricle.
The left ventricle contracts, pushing the blood into the aorta.

23. Circulation of Blood Systemic Circulation
The movement of blood to and from the heart.
It delivers oxygen and nutrients to the tissues of the body and the movement of deoxygenated blood and waste products to the heart.

24. Circulation of Blood Coronary Circulation
The movement of blood through the tissues of the heart.
Serious heart damage may occur if the heart tissue does not receive a normal supply of food and oxygen.

25. Blood Pressure
Blood pressure is a measurement of the amount of force that the blood places on the walls of blood vessels, particularly large arteries, as it is pumped through the body.

26. Blood Pressure
Systolic Pressure – the maximum pressure as your heart contracts to push blood into your arteries.
Diastolic Pressure – the pressure at its lowest point where your heart is relaxed.

27. Blood Pressure
A healthy person’s blood pressure will vary within the normal range of 120/80.
Blood pressure above 140/90 is considered high and places a strain on the heart and can lead to cardiovascular disease.

28. Blood Types
There are two distinct chemical molecules, called antigens, present on the surface of red blood cells.
Blood type is determined by the presence or absence of these antigens.
Type A – “A” antigen present
Type B – “B” antigen present
Type AB – Both antigens present
Type O – Neither antigen present

29. Blood Types
If two different blood types are mixed together, the blood cells may clump together in the blood vessels, causing a potentially fatal situation.
It is important that blood types be matched before blood transfusions take place.
In an emergency, type “O” blood can be given because it is most likely to be accepted by all blood types. However, there is still a risk.

30. Rh Factor
Most blood also contains a certain protein called the Rh factor.
If your blood contains this protein, you are referred to as Rh positive.
Blood that doesn’t contain this protein is called Rh negative.

31. Rh Factor and Pregnancy

32. Care & Problems of the CV System
Follow a well-balanced diet low in saturated fats, cholesterol, and salt
Maintain a healthy weight to reduce stress on the heart, blood vessels and lymph vessels
Participate in regular aerobic exercise at least 30 minutes three or four times per week.

33. Care & Problems of the CV System
Avoid the use of tobacco products and exposure to secondhand smoke.
Avoid illegal drugs, including stimulants, marijuana, and ecstasy.

34. Problems of the Cardiovascular System

35. Congenital Heart Defects
Congenital is any condition that is present at birth.
One common type is a septal defect, in which a hole in the septum allows oxygenated blood to mix with deoxygenated blood and affects the pumping efficiency of the heart.

36. Congenital Heart Defects
Other defects include valves which may not function properly, or the aorta may be abnormally narrow, reducing the amount of blood flowing to the body.

37. Congenital Heart Defects
In many cases the cause of a congenital defect is unknown, but the use of alcohol and other drugs, or certain infections during pregnancy may be associated with heart defects in newborns. It may also be hereditary.
Most defects require medication and possibly surgery to repair the affected portion of the heart.

38. Cardiovascular Disease
A group of diseases that include hypertension, heart disease, and stroke.
It is the number one killer of both men and women among all racial and ethnic groups in the U.S., killing about 95,000 Americans each year.
Many of these diseases are associated with lifestyle behaviors.

39. Heart Murmur
Abnormal sounds that are made as blood flows through the heart.
It can be caused by a defective valve that is too narrow causing blood to be pushed through the restricted opening with more force than normal, or a valve that doesn’t close properly allowing blood to leak back through it.
Most murmurs are slight and disappear without treatment, while others may require surgery

40. Varicose Veins
Varicose veins form if the valves in veins do not close tightly enough to prevent backflow of blood, causing the veins to become large and painful.
They most commonly occur in the legs.
Weakened valves can be the result of a congenital defect, or natural aging.

41. Varicose Veins Physical activity helps prevent varicose veins.
Treatment includes
reducing standing time
Exercise
Elevating legs when sleeping
In extreme cases, surgery to remove the affected vein.

42. Anemia
A condition in which the ability of the blood to carry oxygen is reduced.
It can result from low numbers of red blood cells or from low concentrations of hemoglobin in the blood.
The most common cause is iron deficiency, which can be avoided by eating foods high in iron.
Taking an iron supplement may also be recommended.

43. Anemia
Sickle cell anemia is a special form of anemia where the red blood cells are sickle shaped. They are stiff and sticky and tend to clump and block blood flow in the blood vessels of the limbs and organs, causing pain.

44. Leukemia
A form of cancer in which any one of the different types of white blood cells is produced excessively and abnormally.
The abnormal white blood cells cannot function properly, making the patient very susceptible to infection

45. Leukemia
The uncontrolled production of white blood cells can hinder production of red blood cells and platelets resulting in infection, severe anemia, or uncontrolled bleeding.

46. Leukemia Treatment options include: Chemotherapy Radiation therapy
Bone marrow transplants

47. Hemophilia
An inherited disorder in which the blood does not clot properly.
Certain proteins, called clotting factors, are not present.
This may cause uncontrolled bleeding that can occur spontaneously, or as the result of injury.

48. Hemophilia
Bleeding may take place internally in muscles, tissues of the digestive or urinary tract, and the joints.
It may also occur externally as the result of injury or surgery.

49. Hemophilia
Treatment includes injections that introduce the missing clotting factors into the blood, which are extracted from blood donated by healthy individuals.