Red Blood Cell Functions Quiz

The total blood volume in adults is approximately 80 mL/kg in males and 70 mL/kg in females.

Blood maintains a constant environment for body cells with homeostatic mechanisms keeping blood volume and constituent concentrations stable.

Whole blood consists of water, plasma, and blood cells. Plasma is the liquid component carrying dissolved and suspended substances.

Plasma proteins make up about 7% of plasma and maintain osmotic pressure, have roles in carrier functions and clotting, and are primarily formed in the liver.

Albumin is the most abundant plasma protein, maintaining osmotic pressure and serving as a carrier for fatty acids, drugs, and steroid hormones.

Globulins have functions as antibodies, hormone and mineral salt transport, and enzyme inhibition.

Immunoglobulins are antigen-neutralising antibodies, while thyroglobulin, transferrin, and a2macroglobulin have transport and enzyme inhibition roles.

Clotting factors are responsible for coagulation, with fibrinogen being the most abundant, and are removed from plasma to create serum.

Electrolytes are essential for various bodily functions, including muscle contraction and nerve impulse transmission.

Water makes up 90-92% of plasma, while plasma proteins (7%) and other constituents account for the rest.

Nutrients and waste products are transported in the bloodstream, while hormones are secreted into the blood and transported to target tissues and organs.

Oxygen is transported in the blood mainly bound to haemoglobin in red blood cells, while carbon dioxide is converted to bicarbonate and transported in plasma.

Haemopoiesis is the process of blood cell formation, which takes place in red bone marrow for the first few years of life, with the process being confined to flat bones, irregular bones, and long bone ends in adults.

Erythrocytes (red cells) are responsible for oxygen transport, leukocytes (white cells) are part of the immune system, and platelets (thrombocytes) play a role in blood clotting.

Red marrow is where most blood cells are synthesised, but over the next 20 years, it is largely replaced by fatty yellow marrow, and haemopoiesis is confined to specific sites in adult bones.

Red blood cells are classified based on various systems, including the Wright-Giemsa staining method, which distinguishes between normochromic and anychromic cells.

White blood cells are categorised into five main types: neutrophils, lymphocytes, monocytes, eosinophils, and basophils, each with distinct roles in the immune response.

Platelets contribute to blood clotting by releasing platelet-derived growth factor and other clotting factors, and by aggregating at injury sites to form platelet plugs.

The structure of red blood cells includes a biconcave disc shape facilitating efficient gas exchange, a rigid membrane, and a central nucleus that disappears during maturation.

White blood cells are larger than red blood cells and contain a nucleus, which allows for various functions such as phagocytosis and immune response.

Leukopenia (low white blood cell count) and leukocytosis (high white blood cell count) are conditions that can impact the immune system's ability to fight infections.

Platelet disorders, such as thrombocytopenia (low platelet count) and thrombocytosis (high platelet count), can lead to bleeding or clotting issues.

The Rhesus (Rh) antigen, or Rhesus factor, is a red blood cell membrane antigen important for blood typing. About 85% of people have this antigen, making them Rhesus-positive (Rh+), and do not produce anti-Rh antibodies. The remaining 15% are Rhesus-negative (Rh-), capable of making anti-Rh antibodies under specific conditions, such as pregnancy or incompatible blood transfusions.

The ABO system of blood grouping includes the following antigens and antibodies:

Type A: produces anti-B antibodies and is compatible with A and AB, but incompatible with B and O.

Type B: produces anti-A antibodies and is compatible with B and AB, but incompatible with A and O.

Type AB: produces neither anti-A nor anti-B and is compatible with all groups.

Type O: produces both anti-A and anti-B antibodies and is compatible only with O.

Leukocytes, or white blood cells, are important for defence and immunity. They are the largest blood cells and account for about 1% of blood volume. There are two main types: granulocytes (neutrophils, eosinophils, and basophils) and agranulocytes (monocytes and lymphocytes).

Granulocytes (polymorphonuclear leukocytes) follow a common line of development during granulopoiesis, with multilobed nuclei and distinctive granules.

Neutrophils: small, fast cells that protect against bacterial invasion, attract large numbers to infection sites, and kill bacteria through phagocytosis. They live on average 6-9 hours.

Eosinophils: less active in phagocytosis but eliminate parasites and promote inflammation in allergic reactions through the release of toxic chemicals.

Basophils: closely associated with allergic reactions, contain heparin, histamine, and other chemicals, and play a role in the inflammatory process.

Eosinophils are less active in phagocytosis but eliminate parasites and promote inflammation. They release toxic chemicals when they bind to infecting organisms, and increase in allergic inflammation, such as asthma.

Leukocytes, especially neutrophils, are essential for fighting infections and removing damaged tissue cells and debris. They are attracted to infection sites through chemotaxis and use diapedesis to move through capillary walls.

The ABO system of blood grouping determines the presence or absence of antigens A and B on red blood cells and the corresponding antibodies in the plasma. Incompatible blood transfusions can cause severe reactions, including hemolysis and immune responses.