1. Chapter 15:
Blood

2. What Blood Does Three general functions:
Transportation: oxygen, carbon dioxide, nutrients, hormones
Regulation: body temperature, fluid and electrolyte balance
Protection: WBCs and platelets

3. Composition of Blood Characteristics: Type of connective tissue
Color varies with oxygenation
pH between 7.35 to 7.45
Viscosity: thickness or stickiness compared to water (more viscious)

4. Composition of Blood (cont’d.)
Two Parts:
Plasma: pale, yellow fluid composed mostly of water
Blood cells (formed elements):
Red blood cells (RBCs)
White blood cells (WBCs)
Platelets

5. Hemopoiesis Process of blood cell formation Hemopoietic tissue:
Red bone marrow: found in the end of long bones, flat and irregular bones
Lymphatic tissue: spleen, lymph nodes and thymus

6. Myelosuppression
Condition in which bone marrow cannot produce enough blood cells
Myelosuppression can result in:
Aplastic anemia: RBC deficiency
Leukopenia: WBC deficiency
Thrombocytopenia: Platelet deficiency

7. Polycythemia Vera
Bone marrow overactivity leads to excess RBC production
Caused by a gene mutation
Excess thickened blood:
Burdens the heart
Overwhelms clotting system
Causes beet-red face
Treatment: drugs to suppress bone marrow and/or phlebotomy

8. Red Blood Cells Red blood cells (RBCs): Also called erythrocytes
Most numerous of the blood cells
Primarily responsible for the transport of oxygen and carbon dioxide
Large, disc-shaped, thick outer rim, thin center, bendable
Filled with hemoglobin (iron containing protein)
Color changes from bright red to blue-red

9. Sickle cell disease
Genetic disorder characterized by RBCs that form an abnormal, rigid, C-shape.
Blocks blood flow and restricts tissue of oxygen.

10. Hemoglobin
Iron containing protein in RBCs that transports oxygen and carbon dioxide
Heme: iron containing substance (O² attaches)
Globin: protein (CO² attaches)

11. Regulation of RBC Production
Low O²
Kidneys release erythropoietin (EPO) (hormone)
Stimulates bone marrow to produce RBCs
O² levels increase
EPO no longer released

12. Recycle! Worn out RBCs are broken down into:
Heme: iron (used later) and bile (excreted)
Globin: amino acids (used later for proteins)

13. White Blood Cells White blood cells (WBCs):
Large, round cells that contain nucleus
Also called leukocytes
Function to protect the body
Can leave the blood vessels

14. White Blood Cells (cont’d.)
Type of WBC
Function of Cell
Granulocytes
Neutrophils
Eosinophils
Basophils
Agranulocytes
Lymphocytes
Monocytes
Phagocytosis
Inflammatory responses; allergies
Inflammatory responses; release of heparin
Immunity

15. White Blood Cells (cont’d.)

16. Platelets Platelets: Tiniest blood cells Produced in red bone marrow
Also called thrombocytes
Life span is 5 to 9 days
Function to prevent blood loss

17. Blood Diagnostic Tests
Differential white blood cell count: indicates the percentage of each type of white blood cell
Complete blood count (CBC): lists the normal ranges of the numbers of RBCs, WBCs, and platelets in blood

18. Hemostasis: process that stops bleeding
Vascular spasm: decreases the diameter of the blood vessel
Platelet plug: platelets stick together and adhering to the lining of the injured vessel
Coagulation: clotting of blood to seal off the opening in an injured blood vessel (caused by a series of chemical changes in blood)

19. Blood Types: ABO Grouping
Four blood types: A, B, AB, O
Agglutination: clumping together of RBCs; causes hemolysis (bursting of RBCs)
Compatible blood groups: blood types that mix without undergoing agglutination reactions
Universal donor: type O blood
Universal recipient: type AB blood

20. Blood Types: Rh Factor
Rh factor: an antigen located on the surface of the RBC
About 85% of people are Rh-positive (+)