Download Chapter 37- The Circulatory System

Chapter 37- The Circulatory System
Actually 2 Systems in 1
1. Circulatory System- composed of heart, arteries, veins, capillaries and blood
2. Lymphatic System- composed of lymph and interstial fluid, fights disease and
infection
Functions
1. Carry nutrients from small intestine and oxygen from lungs to the cells of the body
2. Transport waste from cells to kidney, lungs and skin
3. Transport hormones from endocrine glands to cells
4. Control water level in cells
5. Provide antibodies and WBC (white blood cells) to prevent infection
6. Provide materials to clot blood
7. Carry enzymes
8. Distribute heat from metabolism
Blood
45% solids (RBC, WBC, Platelets)
55% plasma (90-92% water, some proteins, dissolved nutrients)
What color is blood ? RED
BLOOD CELLS
Red Blood Cells- a.k.a. RBC, Red Corpuscles, Erythrocytes
Disc or saucer shaped
No nuclei
1/3 hemoglobin- combines with oxygen
Produced in Red Marrow- live 100-120 days, then removed by spleen
White Blood Cells- a.k.a.- WBC, White Corpuscles, Leukocytes
Have nuclei
Colorless
Larger than RBC
1 WBC for every 600 RBC
Destroy infections by phagocytes
Platelets
Form blood clots
Fragments of cells formed in Red Marrow
Less produced than RBC
Combines with other plasma proteins to create a clot
Platelet + Plasma Protein = Thrombin
Thrombin + Fibrinogen (plasma protein) = Fibrin
Fibrin
Clot