Composition of Blood

Study Notes

Composition of Blood

Blood is a complex connective tissue composed of formed elements (cells and cell fragments) suspended in a fluid matrix called plasma.
Plasma, the liquid portion, accounts for about 55% of blood volume and is primarily water.
Dissolved substances in plasma include proteins (albumin, globulins, fibrinogen), nutrients, electrolytes, hormones, gases (oxygen, carbon dioxide), and waste products.
Formed elements include red blood cells (erythrocytes), white blood cells (leukocytes), and platelets (thrombocytes).
Red blood cells are responsible for oxygen transport, while white blood cells fight infection, and platelets help stop bleeding.

Erythrocytes (Red Blood Cells)

Erythrocytes are biconcave discs that lack a nucleus and mitochondria, maximizing their surface area for gas exchange.
They contain hemoglobin, a protein that binds oxygen and carries it throughout the body.
Hemoglobin gives blood its red color.
Erythrocytes have a lifespan of approximately 120 days.
New red blood cells are constantly produced in the bone marrow to replace old and damaged ones.

Leukocytes (White Blood Cells)

Leukocytes are crucial components of the immune system.
They are responsible for defending the body against infections and foreign invaders.
Leukocytes are categorized into granulocytes (neutrophils, eosinophils, basophils) and agranulocytes (lymphocytes, monocytes).
Granulocytes have granules in their cytoplasm, while agranulocytes do not.
Each type of white blood cell plays a specific role in immunity and inflammation.

Thrombocytes (Platelets)

Platelets are cell fragments that play a vital role in blood clotting.
They help prevent blood loss from damaged blood vessels.
Platelets release clotting factors and proteins that form a fibrous network to stop bleeding at a site of injury.
The process involves a cascade of chemical reactions.

Blood Types

Blood is categorized into different types based on the presence or absence of certain antigens on the surface of red blood cells.
The most common blood typing system is the ABO system, which categorizes blood into A, B, AB, and O types.
Incompatible blood transfusions can lead to serious complications.
The Rh factor is another important blood group system classifying blood as Rh positive or Rh negative, influenced by the presence or absence of the Rh antigen.

Blood Functions

Transporting oxygen and nutrients to tissues and removing waste products.
Regulating body temperature and pH.
Protecting the body from pathogens and foreign substances through the immune system.
Clotting to prevent blood loss.
Maintaining homeostasis by transporting hormones and other signaling molecules.

Blood Disorders

Anemia is a condition characterized by a deficiency of red blood cells or hemoglobin.
Leukemia is a type of cancer that affects white blood cells, characterized by uncontrolled proliferation of abnormal white blood cells.
Thrombocytopenia is a condition in which the number of platelets is too low.
Hemophilia is an inherited disorder that impairs the blood's ability to clot.

Blood Circulation

Blood circulates throughout the body in a closed system of blood vessels (arteries, veins, and capillaries), driven by the pumping action of the heart.
Arteries carry oxygenated blood away from the heart, whereas veins carry deoxygenated blood back to the heart.
Capillaries are the smallest blood vessels where gas and nutrient exchange occurs between the blood and surrounding tissues.

Description

Explore the intricate structure and function of blood in this quiz. Understand the roles of plasma and formed elements, including erythrocytes and their importance in oxygen transport. Test your knowledge on how blood contributes to overall health and functionality.