Blood Function and Components

The main function of blood is to transport substances throughout the body, including gases like oxygen and carbon dioxide, nutrients, waste products, ions, chemical messengers, and heat.

Blood pressure is the force exerted by blood against the walls of blood vessels. It is essential for blood circulation and the delivery of oxygen and nutrients to tissues.

Hydrostatic pressure is the pressure exerted by a fluid, in this case, blood, due to its weight. It varies along the circulatory system, contributing to blood flow.

The movement of blood through the circulatory system is driven by pressure differences. Blood flows from areas of higher pressure to areas of lower pressure.

Blood is classified as a connective tissue because it contains cells (formed elements) embedded in a non-living matrix (plasma).

Formed elements are the cellular components of blood, including erythrocytes (red blood cells), leukocytes (white blood cells), and platelets.

Plasma is the non-cellular, liquid component of blood. It consists of water, electrolytes, proteins, gases, nutrients, and waste products.

Centrifugation is a process that separates blood components by density. It results in layers of plasma at the top, a Buffy coat containing platelets and leukocytes in the middle, and erythrocytes at the bottom.

Serum is the liquid portion of blood that remains after clotting. It is similar to plasma but lacks fibrinogen.

Albumin is a major plasma protein that helps maintain blood volume and pressure, transport substances, and regulate blood viscosity.

Globulins are a diverse group of plasma proteins involved in immunity, transport, and blood clotting.

Fibrinogen is a plasma protein that converts into insoluble fibrin during blood clotting.

Capillaries are the smallest blood vessels responsible for the exchange of substances between blood and tissues.

Hematocrit is the percentage of red blood cells in the blood volume. It is a measure of red blood cell concentration.

Red blood cells are biconcave disc-shaped cells responsible for transporting oxygen throughout the body.

Hemoglobin is a protein found inside red blood cells that binds oxygen and carries it to the tissues.

Oxyhemoglobin is the form of hemoglobin that is bound to oxygen.

Deoxyhemoglobin is the form of hemoglobin that has released oxygen and is ready to pick up more.

Carbaminohemoglobin is the form of hemoglobin that is bound to carbon dioxide, carrying it to the lungs for exhalation.

Neutrophils are the most abundant type of white blood cell. They are phagocytes that engulf and destroy bacteria and other pathogens.

Eosinophils are white blood cells that release toxic substances to combat parasitic worm infections and allergies.

The spleen is the organ responsible for detecting and breaking down weakened red blood cells.

Bilirubin is a yellow pigment produced when hemoglobin breaks down. It is excreted from the body in bile.

Lymphocytes are white blood cells involved in adaptive immunity. They produce antibodies and target specific pathogens.

Platelets are small, cell-like fragments essential for blood clotting by releasing factors that initiate blood clotting.

Megakaryocytes are large bone marrow cells that produce platelets.

Erythropoietin (EPO) is a hormone produced by the kidneys that stimulates the production of red blood cells.

The typical lifespan of a red blood cell is about 120 days.