F UNCTION Blood carries the following to the body tissues: Nourishment. Electrolytes. Hormones. Vitamins. Antibodies. Heat Oxygen.

F UNCTION Blood carries the following away from the body tissues:  Waste matter.  Carbon dioxide

C OMPONENTS OF B LOOD

ComponentsFunctions Water (90%) Solvent for other substances Ions ( calcium, sodium, potassium, bicarbonate) Osmotic balance, pH buffereing (7.4), Maintaining ion concentration of interstitial fluid. Plasma proteins; Fibrinogen Immunoglobulins Albumin Osmotic balance and pH buffering Clotting Defense Makes the blood viscous P LASMA (55%)

Cellular elements (45%) Cell typeNumber per  L (mm 3 ) of blood) Functions Transport of O 2 and some CO 2 5–6 million Red blood cells (erythrocytes) White blood cells (leukocytes) 5,000–10,000Defense and immunity Platelets 250,000– 400,000 Blood clotting Basophils Eosinophils Lymphocytes Neutrophils Monocytes

R ED B LOOD C ELLS (E RYTROCYTES ) Increase surface area ; allows more oxygen to diffuse in and out of the cells. Red blood cells do NOT have a nucleus ; allows more room within the cells for hemoglobin.

R ED B LOOD C ELLS (E RYTHROCYTES )

W HITE B LOOD C ELLS (L EUKOCYTES ) 5 major types;

F UNCTIONS Function inside and outside the circulatory system and fight infections and cancer. They can be put into two main groups: 1. phagocytes or macrophages 2. lymphocytes

P HAGOCYTES Phagocytes move through the body’s tissues destroying pathogens and their toxins. ingest and absorb the pathogens or toxins release an enzyme to destroy them.

L YMPHOCYTES Carry antibodies that can recognise particular types of pathogen.

S YNTHETIC EPO I NJECTION Cyclist Lance Armstrong National and world champion cyclist. Two time Olympian, and at one stage 7-time winner of Le Tour de France. Armstrong then admitted to taking performance-enhancing drugs Erythropoietin (EPO)

DANGERS

A NEMIA Anemia can be caused by low amounts of Hemoglobin or Red blood cells. Excessive blood loss Vitamin and mineral deficiencies Certain forms of cancer Iron deficiency Page:480

Anemic person feels tired due to oxygen deficiency in tissues.

P LATELETS Round biconvex cell fragments that do not have a distinct nucleus. First response to body injury is construction of that blood vessel; To decrease blood loss, To allow time for repearing. Then clotting.

B LOOD C LOTTING Figure 23.14A_s3 321 Platelets adhere and release chemicals. A platelet plug forms. Fibrinogen Fibrin A fibrin clot forms. Epithelium Connective tissue Platelet Platelet plug Fibrin clot

Within an hour after a fibrin clot forms; The platelets contract, Pull the torn edges closer together, Reducing size of repearing area. Platelets release chemicals to situmulate cell division in smooth muscle for healing process.

D ANGERS IN BLOOD CLOTTıNG Hemophilia Paralysis or inner bleeding in organs. Asprin, heparin and warfarin are anticoagulant drugs which are used to prevent undesirable clotting in patients at risk for heart attack or stroke.

S TEM CELL Multipotent stem cell Unspecialized cells which have ability to form multiple types of blood cells.

Figure Lymphocytes Monocytes Neutrophils Eosinophils Basophils Myeloid stem cells Platelets Erythrocytes Lymphoid stem cells Multipotent stem cells (in bone marrow)

L EUKEMIA Extra white blood cells do not mature normally. They tend to live well beyond their normal life span. These leukemia cells are unable to fight infection the way normal white blood cells do. They interfere with vital organ functions, including the production of healthy blood cells. May be treated by the replacement of cancerous bone marrow with healthy bone marrow.

I S IT ETHıC ? Is it acceptable to have a child to provide bone marrow donation to a child with leukemia? Why or why not?