Blood and Immune [Blood Components & Function]

Question 1

3 components produced by centrifugation

Answer 1

Packed red cells 40%
Buffy coat 10% WBC
Plasma 50% soluble proteins, lipids, platelets.

Question 2

Albumin

Answer 2

Made by liver. Osmotic pressure between blood and surrounding tissues. Bonds and transports small molecules & hormones. Protein sponge - absorbs fluid in blood. Hyper tonicity.

Question 3

Immunoglobulins

Answer 3

Antibodies. Diverse repertoire of antigen binding proteins. Produced by plasma cells. Found in Y fraction. Becomes elevated in diseases such as multiple myeloma.

Question 4

What do common myeloid progenitors give rise to? What type of immunity?

Answer 4

Myeloid: erythrocytes, mast, megakarycytes (=thrombocytes), myeloblast (=Phils and monocyte which becomes macro)

Innate immunity.

Question 5

What do common lymphoid progenitors give rise to?

Answer 5

Lymphoid: killer cell, small lymphocyte (=T and B. B become plasma cells.)

Adaptive immunity.

Question 6

GM-CSF

Answer 6

Granulocyte macrophage colony-stimulating factor.
Made by T cells, endothelial cells, macrophages, fibroblasts.
Stimulates production of phils + monocytes.

Question 7

G-CSF

Answer 7

Granulocyte colony-stimulating factor.
Produced by many different cells.
Stimulates production of granulocytes and matures neutrophils.

Question 8

What is C3?

Answer 8

The most abundant complement protein in serum.

Question 9

What is electrophoresis and what does it do?

Answer 9

Separation of blood using electric field. Separates serum into 5 protein fractions - albumin, A1, a2, B and Y.

Question 10

What is plasma?

Answer 10

The viscous liquid fraction of blood without cells. Contains fibrinogen that is removed withal coagulation.

Question 11

What carries oxygen from the lungs to tissues?

Answer 11

Haemoglobin, the major protein in RBC.

Question 12

How does haemoglobin get O2 to tissues?

Answer 12

Under the pO2 of oxygen in the lungs, O2 freely binds to Fe2+ in the haemoglobin molecule. When the pO2 drops in the tissue, O2 dissociates and is replaced by CO2.

Question 13

Classical pathway for complement

Answer 13

Antibodies bind to the surface of a microbe. C1-4 condense on the antibody to form C3 convertase on the microbe surface.

Question 14

Complement: What are convertases?

Answer 14

Deposited complexes that activate more complement that then coats the surface. Convertases are bound through a covalent bond.

Question 15

Complement: What are anaphylotoxins and what produces them?

Answer 15

Anaphylatoxins are small polypeptides generates by cleavage of larger complement proteins C3-5. They are chemoattractants C3a, C4a, C5a which activate neutrophils.

Question 16

End stage complement

Answer 16

The surface bound convertases activate complement C5-9. This forms a lore that inserts into some bacterial membranes to cause lysis. The pore is called the MAC (Membrane Attack Complex).

Question 17

What are virulence factors?

Answer 17

Proteins produced by microbes that inhibit the complement cascade.

Question 18

Complement: Alternative pathway

Answer 18

Complement C3 is activated just by being close to the surface of a microbe. This activates another type of C3 convertase.

Question 19

Complement: Lectin pathway (and what are lectins?)

Answer 19

Lectins are carbohydrates binding proteins in blood that bind to unusual carbohydrates found only on microbes. Complement condenses on these bound microbes.

Question 20

Coagulation: Intrinsic pathway

Answer 20

Caused by contact with surfaces. Factors 12, 11, 9 and 8 cleave factor X that converts prothrombin to thrombin.

Question 21

Coagulation: Extrinsic pathway

Answer 21

Caused by tissue damage. Factors 7 and tissue factors TF combine to activate factor X.

Question 22

Coagulation: what is plasminogen and what is it converted to?

Answer 22

A protease activates by tissue plasminogen activator (TPA) or streptokinase. Converted to active plasmin which dissolves the clot.

Question 23

Thrombolysis

Answer 23

Dissolving of the clot.

Question 24

Oxyhaemaglobin ligand, colour and condition

Answer 24

O2
Bright red
Normal oxygenated blood

Question 25

Carbamihaemaglobin ligand, colour and function

Answer 25

CO2
Dark red
Venous blood

Question 26

Carboxyhaemaglobin ligand, colour and condition

Answer 26

CO
Cherry red
Carbon monoxide poisoning

Question 27

Cyanohaemaglobin ligand, colour and condition

Answer 27

CN, pink, cyanide poisoning

Question 28

What is a protease?

Answer 28

An enzyme which breaks down proteins etc.