3. Circulatory System
Can be compared to a road map or even a highway system because it has 2 major functions: transportation and elimination
Blood carries food, water, oxygen, etc. through the body to the cells and other tissues
The blood is also responsible for eliminating waste such as carbon dioxide and other wastes produced by cells

5. Circulatory System Organs
The heart is the organ that pushes the blood throughout the circulatory system; average heart rate is beats/minute
The right side of the heart pumps blood to the lungs to receive oxygen, while the left side pumps blood to the entire body
The human body has a 4-chambered heart; top 2 chambers are the atria, bottom 2 chambers are the ventricles

6. Basic path of blood flow:
Right atrium receives oxygen-poor blood from all parts of the body
Oxygen-poor blood flows into the right ventricle and is then pumped to the lungs
The left atrium receives oxygen-rich blood from the lungs
Oxygen-rich blood flows into the left ventricle and is then pumped to the rest of the body

8. Components of Blood
The blood is made up of plasma, red blood cells, white blood cells, and platelets
Plasma is a fluid that contains proteins, glucose, hormones, gases and other substances dissolved in water (60%)
White blood cells help fight infection by attacking disease- causing organisms
Red blood cells are more numerous than white blood cells; they are responsible for picking up oxygen in the lungs and transporting It throughout the body delivering oxygen to other cells
Platelets are large cell fragments that help form blood clots when a blood vessel is injured; they become enlarged and sticky and stick to the injured area, releasing chemicals that result in clotting

10. Blood Vessels
Blood vessels are kind of like side roads in a major city
Arteries have strong walls and take blood away from the heart; an artery wall is thick and elastic to handle the tremendous force produced when the heart pumps
Veins carry blood back to the heart; walls are thinner, but have greater diameter than arteries; lower pressure than arteries
Capillaries connect arteries and veins; deliver supplies to individual cells and take away waste materials; smallest vessel

12. Hypertension
The contractions of the heart push blood through blood vessels (artery) causing pressure to be exerted on the blood vessels (artery)…this is known as blood pressure
If the blood pressure is too high, the force may weaken the blood vessels and require the heart to work harder to push blood through the blood vessels. This is called hypertension.

14. Cardiovascular Disease
Cardiovascular disease deals with the heart and blood vessels, many of which are related to plaque buildup in the arteries called atherosclerosis
Heart disease is the number 1 leading cause of death in the united states and claims more lives than all forms of cancer combined
Coronary heart disease (plaque buildup in coronary arteries) is the most common killing nearly 380,000 annually
In the united states, a person has a heart attack every 34 sec., while every 60 sec. someone dies from a heart-related disease
Heart disease is the number 1 killer for women; 1in 31 will die from breast cancer, while 1 in 3 will die from heart disease
An estimated 43 million women in the united states are affected by heart disease; 90% of women have 1 or more risk factors for developing heart disease