A: Rh factor, Rh positive and Rh negative refer to the D antigen only. If the antigen is present on your RBC, you are called Rh positive (you have the Rh factor).

D: The clotting (coagulation phase) has these two pathways.

B: Thrombin is the enzyme. It is not present until prothrombinase converts prothrombin to thrombin.

B: Antigens are on the surface of RBC. Antibodies (=agglutinins) circulate in the bloodstream and react with their appropriate antigen (agglutination)

B: Leucocytes (white blood cells) include NK (natural killer), T and B lymphocytes and macrophages and microphages.

D: About one third of the mass of a RBC is haemoglobin. Choices A and B are plasma proteins and are not in RBC.

D: Red blood cells contain much haemoglobin which binds to oxygen to transport it to the tissues.

C: Factor X is a plasma protein produced by the liver. In the extrinsic pathway, factor III combines with factor VII to form an “enzyme complex” that activates factor X.

A: RBC = erythrocytes (erythroid means red)

C: Osmolality is the number of osmoles (osmol) of solute per kilogramme of solvent. (Osmolarity (with an “r”) is defined as the number of osmoles of solute per litre of solution.)

C: Plasma proteins (except fibrinogen) are in plasma and in serum. Serum = plasma minus the clotting factors. Blood cells and platelets are not in plasma.

D: Prothrombinase is made from factor X. It then acts on prothrombin to form thrombin

B: Less than 1% of WBC are basophils. Neutrophils are the most common. Thrombocytes are not WBC.

A: An erythrocyte is a red blood cell.

D: The extrinsic and intrinsic pathways form “prothrombinase” (also called prothrombin activator) from factor X.

C: Neutrophils do have a nucleus but don’t have haemoglobin. Eosinophils are a type of WBC as are neutrophils, but they are not the same.

A: Keratin is the protein that the stratum corneum of the skin, hair and nails are made of.

A: Only leucocytes (WBC) possess a nucleus from which DNA may be sampled. Erythrocytes are anucleate (absence of nucleus).

A: Formed elements are the nonliquid or solute parts of the blood.

B: About 58% of plasma proteins are albumins. Haemoglobin is a protein but it is contained within the RBC.

B: Antigens are on the membrane of the RBC. The other three terms all describe the same thing, antibodies that are circulating in the plasma.

A: Their blood contains anti-B agglutinins. If you have the A antigen on your RBC, you cannot have the anti-A agglutinin in your plasma or you would agglutinate your own blood

D: The three phases are vascular phase, platelet phase and coagulation phase (which, in turn, has three steps).

C: People with AB+ blood do not have agglutinins (antibodies) against A, B or Rh D in their plasma. Hence they can receive any blood without causing the RBC in the donated blood to clump (agglutination).

B: Neutrophils are microphages – phagocytes of bacteria. Thrombocytes and erythrocytes are not WBC.

D: A patient that is B+ may receive B+, B−, O+ or O− blood because those types do not have antigen A on the donated RBC.

C: Almost immediately (within 2 s) after a blood vessel is cut, the vessel walls contract in a spasm to slow the flow of blood (vessel diameter decreases).

C: Fibrin is a monomer that polymerises to form a “soft clot”, and then crosslinking between fibrin produces a stable, web-like “hard clot”.

C: If the recipient’s antibodies attack the donated RBC, agglutination will occur. The reverse (choice D) is not a problem.

D: A megakaryocyte is the cell that produces the membrane-covered cell fragments known as platelets. It is not a macrophage. A dendrocyte is also known as a Langerhans cell or a granstein cell.