BLOOD

PHLEBOTOMIST person trained to draw blood from a patient for clinical or medical testing, transfusions, donations, or research.

Hematophobia = fear of blood Blood is the medium that transports all substances that must be carried or transported from one place to another within the body. Hematophobia = fear of blood

Blood and Blood Cells Blood is a type of CONNECTIVE TISSUE It has two basic components: CELLS  (rbc, wbc, platelets)  = 45% Plasma (water, proteins, amino acids..etc)  = 55%

PLASMA: Plasma proteins: Albumins --- 60% of plasma proteins. Regulate osmotic pressure; transport lipids and steroid hormones. Dominate plasma proteins Globulins --- 35% of plasma proteins. Transport ions, hormones, lipids; immune function. Used to make antibodies. Fibrinogens --- 4% of plasma proteins. Work for clotting system. Regulatory proteins --- <1% of plasma proteins. Regulate enzymes, proenzymes, and hormones. For blood contents. Electrolytes (Ions): Na+, Ca2+, Mg2+, Cl-, HCO3-, HPO42- Organic wastes: Urea, uric acid, creatinine, bilirubin, ammonium ions

Three Types of Blood Cells erythrocytes = red blood cells leukocytes = white blood cells thrombocytes= platelets

RED BLOOD CELLS: Dominate cell in the body. Structure: - 7.5 um in diameter, shaped like biconcave discs, which is flattened ones with depressed centers; without nucleus. - Color: salmon red to pale pink. - 4 - 6 millions RBCs/mm3. 1 drop of blood. Each RBC circulates 120 days. - RBCs contain hemoglobin (protein) which can load O2. 1) When O2 binds to Fe2+ of hemoglobin, the case is called oxyhemoglobin. 2) When O2 detached Fe2+ of hemoglobin, the case is called deoxyhemoglobin. E.x. Anemia --- Reduced oxygen-carrying ability of blood resulting from too few RBCs or abnormal hemoglobin.

Main Functions of RBCs Transport 98% O2 and 10-20% CO2. Utilizes HEMOGLOBIN – a four chain protein molecule that works with IRON to combine with O2   Transport 98% O2 and 10-20% O2

HEMATOPOEISIS – formation of blood cells -- occurs in the bone marrow Old blood cells are destroyed by the liver & spleen - phagocytosis

EPO, or erythropoietin, is a hormone that increases production of RBC’s. In the first part of a two-night interview broadcast Thursday, disgraced cyclist Lance Armstrong admitted to Oprah Winfrey that he took banned substances, including EPO, during all seven of his Tour de France victories. What is EPO? (Gizmodo Article)

Blood cells are produced in the bone marrow: RBC Production: Blood cells are produced in the bone marrow: - At the embryo, blood cells are produced in the yolk sac, liver, spleen, and bone marrow. - From birth to age five, blood cells are produced in all the bones of skeleton. - After age five, the pelvis, spine, ribs, cranium, and proximal ends of long bones produce blood cells. Red Marrow is the main site of blood cell formation throughout adult life. T-lymphocytes are produced in the bone marrow and matured in the thymus. Red blood cells recycle: -Amino acids from the globin chains become new protein;   -Some iron from heme groups may be reused in new heme groups. -The old heme is converted by cells of the spleen and liver to a colored pigment (yellow) called bilirubin .

Hematopoiesis is controlled by cytokines: Cytokines include: Erythropoietin (EPO) --- It is a hormone and produced in the kidney. Stimulates the production of red blood cells. Thrombopoietin (TPO) --- It is produced in the liver. Stimulates platelets. Colony-stimulating factors --- It is made by endothelium and fibroblasts of bone marrow. Stimulates white blood cell production. Interleukins --- It is released by leukocytes. Stem cell factor --- from stem cells.   EPO regulates red blood cell production --- Red blood cell production is controlled by EPO. The low oxygen levels in the tissue (hypoxia) stimulate the kidneys releasing EPO. When O2 level is too high, no effect is produced.

Oxygen Levels Oxyhemoglobin = plenty of oxygen; “bright red” Deoxyhemoglobin =         low in O2, “dark red”

It is a myth that deoxygenated blood appears blue.  The blood on the left is oxygenated, the right is deoxygenated blood (from a vein) Source:  Wikipedia Commons

Elements Critical to RBC Production Folic Acid Vitamin B12 Iron Too few RBC = anemia

WHITE BLOOD CELLS (Leukocytes) General function is to protect the body against disease There are FIVE different kinds of WBCs Granulocytes (granular cytoplasm)           Neutrophils, Eosinophils, Basophils Agranulocytes (lacking granular cytoplasm)            Monocytes, Lymphocytes

The white blood cells are found within the red blood cells, there are not as many WBC’s and generally, they are larger than RBC’s.

Neutrophil 50 -70% of WBCs. Nucleus consists of 3-7 lobes Present in the pus of wounds Engulf pathogens (Bacteria) or debris in tissues; survive mins to days.

Eosinophil Mainly attack parasites 2-4% of WBCs. Nucleus has two lobes Engulf antibody-labeled material; survive mins to days. Number rises during parasite infection

Basophil <1% of WBCs. Nucleus generally cannot be seen. If it can be seen, usually it shows a "U" of "S" shaped nucleus Histamines = Important in Inflammatory Reaction Important for blood clotting Writing on Legs

Dermatographia: Immune system releases excess amounts of histamine causing welts to appear when lightly scratched. Cold Urticaria (essentially meaning "cold hives") is an where hives or large red welts form on the skin after exposure to a cold stimulus.

Monocyte 2-8% of WBCs. Kidney-shaped nucleus, pale blue cytoplasm. Become macrophages Engulf pathogens or debris; survive for months or longer; increase in number during prolonged infection First line of defense at infection site.

Lymphocyte (nucleus is dark and takes up almost whole cell) LYMPH NODES Lymphocyte (nucleus is dark and takes up almost whole cell) Main defense (immune system) Produce ANTIBODIES 30% WBC

Left: Lymphoctye | Right: Neutrophil

Platelets (thrombocytes) Blood clots and vessel repair

PLASMA The liquid portion of blood is 92% water Also contains nutrients, gases, vitamins (etc) and plasma proteins

Plasma Proteins Albumins – blood pressure Globulins – transport lipids and antibodies for immunity Fibrinogen – important for blood clotting

This machine removes the plasma from the blood and returns the RBC’s to the donor.

HEMOSTASIS The process of stopping bleeding Involves the coagulation and clotting of the blood to seal the site of damage

*thrombin is an enzyme that causes the conversion THREE EVENTS IN HEMOSTASIS 1.  Blood Vessel Spasm      Seratonin = vasoconstrictor 2.  Platelet plug formation   = plugs opening 3.   Blood coagulation conversion of fibrinogen to fibrin *thrombin is an enzyme that causes the conversion

COAGULATION  -  the thickening of blood to form a clot  (hematoma)

THROMBUS – blood clot (abnormal) EMBOLUS – when the clot moves to another place. * Cerebral Embolism - when a blood clot goes to the brain * Pulmonary Embolism - when a blood clot goes to the lungs