Circulatory System

Red blood cells: most abundant cells; contain hemoglobin; carry oxygen through the body White blood cells: fight off infection, bacteria, viruses, etc. Plasma: yellowish liquid that is 90% water; carries nutrients to cells and waste away from cells; contains red blood cells, white blood cells, and platelets Platelets: cause the blood to coagulate so you don’t bleed to death

The spleen acts as a filter, trapping bacteria and viruses that are transported thorough the blood. It is a disposal site for worn out red blood cells. The liver (largest organ) breaks down dead cells and reuses them as nutrients. Too much cholesterol can build up on the walls of arteries, causing them to harden and become narrow or blocked. This makes it harder for the blood to flow. This can lead to high blood pressure, which strains the heart.

Red Blood Cells Only last for about 4 months before they die and are replaced by new ones Die at a rate of 8 million a second Dead blood cells float in your blood

Liver Body’s largest organ One of its jobs is to remove dead blood cells Breaks down dead cells and reuses them as nutrients – Nutrients = food

Spleen Acts as a filter Traps bacteria and viruses that are transported through the blood Disposal site for worn out red blood cells

Cholesterol Sources of cholesterol are the liver and food You need SOME to help organs grow and do their jobs Too much of it can be bad…

Cholesterol and Fat Too much cholesterol can cause a buildup on the inside of arteries Causes arteries to become narrow or blocked Less blood flows through and less oxygen gets to the body This leads to high blood pressure, which strains the heart

Heart Attack When an artery supplying blood to the heart gets clogged with plaque, a heart attack occurs and heart tissue dies The heart is not receiving enough oxygen