physiology notes:

Notes: Blood

1. Plasma: straw colored liquid portion of the blood; consists of water and dissolved

solids.

Formed elements: include the cells and fragments of cells suspended in the blood.

2. Plasma components:
   1. solutes: major solute is Na+ but other ions are present; organic molecules

(glucose, amino acids, fats, hormones, enzymes)

2. 2. Plasma proteins: 3 types travel in the blood

(1). Albumins: made in the liver and provide osmotic pressure allowing

fluid to enter the capillaries

(2). Globulins: alpha globulins and beta globulins are made by liver and

They transport lipids and fat soluble vitamins; gamma globulins are

antibodies.

3. Cell types:
   1. Erythrocytes: biconcave discs having no nuclei or mitochondria;

Specialized to transport oxygen; filled with hemoglobin that binds

oxygen; live span= 120 days; old RBC’s removed by phagocytic cells

in liver and spleen.

3. 2. leukocytes: found within the immune system; each has a different function

in fighting pathogens:

(1). Granulocytes

-Neutrophils: 50-70% of WBC’s (polymorphonuclear leukocytes)

Active phagocytes; attack bacteria, fungi. Causes lysis.

-. Eosinophils: 2-4 % of WBC’s; fights parasitic worms; lessens

effect of allergies

-. Basophils: rarest WBC’s; contain histamine (vasodilator)

(2). Agranulocytes

-lymphocytes: 25% of WBC’s; become T and B lymphocytes

-Monocytes: largest leukocytes: become macrophages; phagocytes;

4. Erythopoiesis: formation of red blood cells occurring in myeloid tissue; red bone

marrow with stem cells (erythroblasts) produce cells that will become RBC’s;

when stem cells divide. One daughter cell→RBC, the other remains a stem cell;

5. Erythropoietin: hormone from the kidney; binds to erythroblasts and stimulates them to divide.

6. Blood antigens: protein markers on the surface of red blood cells; help immune

system tell self from non-self; antibodies can bind to antigens and cause the cells

to agglutinate.

7. Agglutinogen: an individuals red blood cell antigen.
8. Agglutinins: preformed antibodies that attack any foreign blood present
9. ABO system: 2 proteins A and B that may be present on the RBC surface; lack

of both proteins= blood type O. The four major groups: A, B, AB, and O.

10. Antibodies: Type A antigens have antibody B

Type B antigens have antibody A

Type AB has neither

Type O has both

11. Rh factor: (from Rhesus monkeys); another protein associated with the RBCs.

having the Rh factor= Rh+; if absent= Rh-.

12. Erythroblastosis fetalis: Rh antibody reaction against the fetus when the developing baby is Rh+ and mother is Rh-; occurs during 2^nd pregnancy and only

if there is a break in placental wall.

13. Blood reaction components:
    1. Platelets (thrombocytes) : initiate the reaction
    2. Thromboplastin: found in platelets
    3. Prothrombin: inactive blood protein
    4. Thrombin: active blood coagulant
    5. Fibrinogen: inactive blood protein
    6. Fibrin: protein strands that form part of blood clot

     

14. ADP: aggregating agent; attracts additional platelets to assist in sealing broken

or damaged blood vessels.

Serotonin: stimulates vasoconstriction

Thromboxane A2: aggregation and vasoconstriction

15. Thromboplastin: released from the platelets when they are cut or damaged

Prothrombin: interacts with thromboplastin to form thrombin

Thrombin: changes fibrinogen into fibrin.

Vitamin K: required for making 4 procoagulants from the liver

Calcium: needed to make procoagulants

16. Clot dissolution: repair of the damaged blood vessel will cause the activation

of plasminogen to plasmin; plasmin will cut the fibrin fibers causing clot

to dissolve.

17. Fibrinolysis: see #16 above
18. Bicarbonate: used as a buffer; pH of blood must remain within narrow range of

Values (7.35-7.45); body uses weak acids/bases that can absorb H+ at low pH

and give up H+ at high pH; main buffer is bicarbonate:

CO2 + H2O →H2CO3

H2CO3→H+ + HCO3-

HCO3- + H+ →H2CO3

19. a. Acidosis: when pH drops below 7.35: H+ builds up in blood

b. Respiratory acidosis: hypoventilation = ↑of plasma CO2→carbonic acid;

emphysema can cause this (retention of CO2)

c. Metabolic acidosis: ↑metabolic acids (ketones from diabetes), or loss of

bicarbonates from pancreatic juice in diarrhea.; may be caused by excess

ingestion of alcohol (forms acetic acid); also ↑lactic acid.

20. Alkalosis: when pH rises above 7.45; OH+ ions begin to build up and proteins

in tissue are dissolved.

21. Respiratory alkalosis: hyperventilation; ↓CO2 levels in blood and removal of

H+ ions; high altitude exercise;

Metabolic alkalosis: ↑HCO3- ; vomiting (loss of H+ in stomach requires

replacement of H+ ions)* See Chart on p. 1054