Blood Composition and Functions

A set of flashcards based on blood composition and functions, covering important concepts such as types of blood cells, blood types, and the clotting mechanism.

What is the average volume of blood in an adult human?

About 4 to 6 liters, which is approximately 7% to 9% of body weight.

What is plasma?

Plasma is blood minus its cells; it contains water and many dissolved substances like foods, salts, and hormones.

What are the formed elements of blood?

The formed elements include red blood cells (RBCs), white blood cells (WBCs), and platelets.

What is the role of hemoglobin in red blood cells?

Hemoglobin transports oxygen and carbon dioxide in the blood.

Define leukopenia.

Leukopenia is an abnormally low white blood cell (WBC) count.

What are the two main types of leukocytes?

The two main types of leukocytes are granular (e.g., neutrophils, eosinophils, basophils) and agranular leukocytes (e.g., lymphocytes, monocytes).

What is polycythemia?

Polycythemia is an abnormally high red blood cell (RBC) count.

What are the stages of blood clotting involving platelets?

Platelets aggregate at the injury site, releasing clotting factors that convert prothrombin to thrombin, leading to fibrin formation and clot creation.

What is the difference between Rh-positive and Rh-negative blood?

Rh-positive blood has the Rh factor antigen present in RBCs, while Rh-negative blood does not have this antigen.

What is the universal donor blood type?

Type O- is considered the universal donor blood type.

What is erythroblastosis fetalis?

Erythroblastosis fetalis is a condition that may occur when an Rh-negative mother carries an Rh-positive fetus, leading to an immune reaction against the fetus's red blood cells.

What are the four main ABO blood types?

The four main ABO blood types are Type A, Type B, Type AB, and Type O.

What determines a person's ABO blood type?

A person's ABO blood type is determined by the presence or absence of specific antigens (agglutinogens) — A and B — on the surface of their red blood cells.

Describe the antigens and antibodies present in individuals with Type A blood.

Individuals with Type A blood have A antigens on their red blood cells and anti-B antibodies in their plasma.

Describe the antigens and antibodies present in individuals with Type AB blood.

Individuals with Type AB blood have both A and B antigens on their red blood cells and no anti-A or anti-B antibodies in their plasma.

What is the universal recipient blood type?

Type AB+ is considered the universal recipient blood type, as individuals with this type have both A and B antigens and lack anti-A and anti-B antibodies, allowing them to receive blood from all ABO and Rh types.

Describe the antigens and antibodies present in individuals with Type B blood.

Individuals with Type B blood have B antigens on their red blood cells and anti-A antibodies in their plasma.

Describe the antigens and antibodies present in individuals with Type O blood.

Individuals with Type O blood have neither A nor B antigens on their red blood cells, but they have both anti-A and anti-B antibodies in their plasma.

What is agglutination and why is it important in blood transfusions?

Agglutination is the clumping of red blood cells caused by an immune reaction between incompatible antigens on RBCs and antibodies in the plasma. It is crucial for blood transfusions because incompatible blood types lead to agglutination, which can cause severe, life-threatening transfusion reactions.

What are the primary functions of neutrophils?

Neutrophils are a type of granular leukocyte that primarily function as phagocytes, engulfing and destroying bacteria and other pathogens at sites of infection. They are crucial for acute inflammation and are the most abundant type of WBC.

What are the primary functions of eosinophils?

Eosinophils are a type of granular leukocyte involved in allergic reactions and defending against parasitic infections. They can phagocytize antigen-antibody complexes.

What are the primary functions of basophils?

Basophils are granular leukocytes that release histamine and heparin at sites of inflammation. Histamine is involved in allergic responses, and heparin prevents blood clotting.

What are the primary functions of lymphocytes?

Lymphocytes are agranular leukocytes crucial for adaptive immunity. They include T cells (involved in cell-mediated immunity) and B cells (which produce antibodies).

What are the primary functions of monocytes?

Monocytes are agranular leukocytes that differentiate into macrophages in tissues. Macrophages are powerful phagocytes that engulf pathogens, dead cells, and cellular debris, playing a key role in chronic inflammation and antigen presentation.