Blood Composition and Functions

Blood Composition

• Types of Cells:

  • Erythrocytes (Red Blood Cells): Transport oxygen and carbon dioxide.
  • Leukocytes (White Blood Cells): Immune response; multiple types (e.g., neutrophils, lymphocytes).
  • Thrombocytes (Platelets): Blood clotting.

• Plasma:

  • Liquid component (about 55% of blood volume).
  • Contains water, electrolytes, proteins, hormones, nutrients, and waste products.

Functions of Blood

1. Transportation:

   • Oxygen from lungs to tissues; carbon dioxide from tissues to lungs.
   • Nutrients from the digestive tract to cells.
   • Hormones from glands to target organs.

2. Regulation:

   • Maintains body temperature, pH balance, and osmotic balance.
   • Helps regulate fluid balance in tissues.

3. Protection:

   • Immune response against pathogens.
   • Clotting mechanisms to prevent blood loss from injuries.

Blood Types

• ABO System:

  • Types: A, B, AB, O.
  • Determined by the presence or absence of antigens (A and B) on erythrocyte surfaces.

• Rh Factor:

  • Positive (+) or negative (-) based on the presence of Rh antigens.

Blood Disorders

• Anemia:

  • Decreased red blood cell count or hemoglobin; leads to fatigue and weakness.

• Leukemia:

  • Cancer of blood-forming tissues; excess immature white blood cells.

• Hemophilia:

  • Genetic disorder characterized by impaired blood clotting.

• Thrombosis:

  • Formation of a blood clot inside a blood vessel, potentially leading to blockage.

Hemostasis (Blood Clotting)

1. Vascular Spasm:

   • Constriction of blood vessels to reduce blood flow.

2. Platelet Plug Formation:

   • Platelets adhere to the site of injury and aggregate to form a temporary plug.

3. Coagulation:

   • Series of biochemical reactions leading to the conversion of fibrinogen to fibrin, solidifying the clot.

Blood Tests

• Complete Blood Count (CBC):

  • Measures levels of red blood cells, white blood cells, hemoglobin, hematocrit, and platelets.

• Blood Typing:

  • Determines ABO and Rh type for transfusions.

• Coagulation Tests:

  • Assess clotting ability (e.g., PT, aPTT tests).

Blood and Disease

• Infectious Diseases:

  • Blood can be a medium for transmission (e.g., HIV, hepatitis).

• Non-infectious Diseases:

  • Conditions like sickle cell disease arise from genetic mutations affecting blood composition.

Blood Composition

• Erythrocytes (Red Blood Cells): Carry oxygen from the lungs to tissues and transport carbon dioxide back to the lungs.
• Leukocytes (White Blood Cells): Key in immune defense with various types like neutrophils and lymphocytes.
• Thrombocytes (Platelets): Essential for blood coagulation and preventing excessive bleeding.
• Plasma: Approximately 55% of blood volume; a yellowish liquid containing water, electrolytes, proteins, hormones, nutrients, and metabolic waste.

Functions of Blood

• Transportation: Distributes oxygen, nutrients, and hormones throughout the body while removing carbon dioxide and waste.
• Regulation: Controls body temperature, maintains pH and osmotic balance, and regulates tissue fluid levels.
• Protection: Defends against infections via immune responses and prevents blood loss through clotting mechanisms.

Blood Types

• ABO System: Classifies blood into four types—A, B, AB, and O—based on specific antigens present on red cell surfaces.
• Rh Factor: Blood type can be positive (+) or negative (-), indicating the presence of Rh antigens on erythrocytes.

Blood Disorders

• Anemia: Characterized by low red blood cell counts or insufficient hemoglobin, resulting in fatigue and weakness.
• Leukemia: A type of cancer affecting blood-forming tissues, resulting in an overproduction of immature white blood cells.
• Hemophilia: A hereditary disorder causing inadequate clot formation, leading to excessive bleeding.
• Thrombosis: The abnormal formation of a clot within a blood vessel, risking blockage and compromising blood flow.

Hemostasis (Blood Clotting)

• Vascular Spasm: Blood vessel constriction occurs immediately following injury to minimize blood loss.
• Platelet Plug Formation: Platelets adhere to exposed tissue and aggregate to form a temporary barrier at the injury site.
• Coagulation: Fibrinogen is converted to fibrin through biochemical reactions, creating a stable clot to prevent further bleeding.

Blood Tests

• Complete Blood Count (CBC): Evaluates red and white blood cell counts, hemoglobin, hematocrit levels, and platelet counts.
• Blood Typing: Determines a person’s ABO and Rh blood type, crucial for safe blood transfusions.
• Coagulation Tests: Analyze the blood's ability to clot (e.g., Prothrombin Time (PT) and activated Partial Thromboplastin Time (aPTT) tests).

Blood and Disease

• Infectious Diseases: Various pathogens can be transmitted through blood, including HIV and hepatitis viruses.
• Non-infectious Diseases: Genetic disorders such as sickle cell disease lead to abnormal blood cell formation and function.

Explore the fascinating world of blood in this quiz covering its composition, functions, and blood types. Learn about the different cells in blood, their roles in transportation, regulation, and protection, as well as the ABO blood type system. Test your knowledge and understand the vital roles blood plays in the human body.