Circulatory system

CIRCULATORY SYSTEM

Overview of the Circulatory System Function:

  • Transports oxygen and nutrients:

    • Delivers essential substances like oxygen and glucose to cells for proper function.

  • Removes waste materials:

    • Clears waste products, such as carbon dioxide and urea, from tissues.

  • Works with the respiratory system:

    • Facilitates gas exchange for efficient oxygen intake and carbon dioxide elimination.

Components:

  • Blood:

    • Carries nutrients, gases, hormones, and waste.

  • Blood vessels:

    • Includes arteries, veins, and capillaries for circulation.

  • Heart:

    • Pumps blood throughout the body.

Structure of Blood Vessels

  • Tunica Adventitia:

    • Outermost layer for support and elasticity.

  • Tunica Media:

    • Middle layer of smooth muscle for regulating blood flow.

  • Tunica Intima:

    • Innermost layer that minimizes resistance to blood flow.

Blood Components

  • Plasma (55%):

    • Liquid part of blood that carries nutrients and waste.

  • Formed Elements (45%):

    • Red blood cells (erythrocytes):

      • Carry oxygen.

    • White blood cells (leukocytes):

      • Fight infections.

    • Platelets:

      • Help with blood clotting.

Functions of Blood

  • Transportation:

    • Carries gases, nutrients, and waste.

  • Protection:

    • Engages in immune responses and prevents blood loss.

Components of Blood Cells

  • Red Blood Cells:

    • Biconcave shape for gas exchange, contain hemoglobin for oxygen transport.

  • White Blood Cells:

    • Protect against infections.

  • Platelets:

    • Assist in clotting.

Heart Structure and Function

  • Chambers:

    • Four chambers - right atrium, left atrium, right ventricle, left ventricle.

  • Valves:

    • Control blood flow between the heart chambers.

  • Function:

    • Heart pumps blood and maintains circulation.

Lymphatic System Function:

  • Collects and recycles fluid, helps in immune response. Components:

  • Lymphatic vessels and lymph nodes act as filters.

Hemostasis Definition:

  • The process that prevents and stops bleeding (hemorrhage). Phases:

  1. Vascular Phase: Immediate constriction of blood vessels to reduce blood flow.

  2. Platelet Phase: Platelets adhere to the damaged endothelium and aggregate to form a temporary plug.

  3. Coagulation Phase: Formation of a fibrin clot through a series of reactions involving clotting factors that stabilize the platelet plug.

  4. Fibrolytic Phase: Breakdown of the clot after healing to restore normal blood flow.

Blood Agglutination Definition:

  • The clumping together of cells, particularly red blood cells, in response to an antigen-antibody reaction. Causes:

  • Occurs during blood transfusions if incompatible blood types are mixed, leading to an immune response. Importance:

  • Critical for blood typing and ensuring safe blood transfusions. If agglutination occurs, it can lead to serious complications, including hemolytic reactions.

CIRCULATORY SYSTEM

Overview of the Circulatory System Function:

  • Transports oxygen and nutrients:

    • Delivers essential substances like oxygen and glucose to cells for proper function.

  • Removes waste materials:

    • Clears waste products, such as carbon dioxide and urea, from tissues.

  • Works with the respiratory system:

    • Facilitates gas exchange for efficient oxygen intake and carbon dioxide elimination.

Components:

  • Blood:

    • Carries nutrients, gases, hormones, and waste.

  • Blood vessels:

    • Includes arteries, veins, and capillaries for circulation.

  • Heart:

    • Pumps blood throughout the body.

Structure of Blood Vessels

  • Tunica Adventitia:

    • Outermost layer for support and elasticity.

  • Tunica Media:

    • Middle layer of smooth muscle for regulating blood flow.

  • Tunica Intima:

    • Innermost layer that minimizes resistance to blood flow.

Blood Components

  • Plasma (55%):

    • Liquid part of blood that carries nutrients and waste.

  • Formed Elements (45%):

    • Red blood cells (erythrocytes):

      • Carry oxygen.

    • White blood cells (leukocytes):

      • Fight infections.

    • Platelets:

      • Help with blood clotting.

Functions of Blood

  • Transportation:

    • Carries gases, nutrients, and waste.

  • Protection:

    • Engages in immune responses and prevents blood loss.

Components of Blood Cells

  • Red Blood Cells:

    • Biconcave shape for gas exchange, contain hemoglobin for oxygen transport.

  • White Blood Cells:

    • Protect against infections.

  • Platelets:

    • Assist in clotting.

Heart Structure and Function

  • Chambers:

    • Four chambers - right atrium, left atrium, right ventricle, left ventricle.

  • Valves:

    • Control blood flow between the heart chambers.

  • Function:

    • Heart pumps blood and maintains circulation.

Lymphatic System Function:

  • Collects and recycles fluid, helps in immune response. Components:

  • Lymphatic vessels and lymph nodes act as filters.

Hemostasis Definition:

  • The process that prevents and stops bleeding (hemorrhage). Phases:

  1. Vascular Phase: Immediate constriction of blood vessels to reduce blood flow.

  2. Platelet Phase: Platelets adhere to the damaged endothelium and aggregate to form a temporary plug.

  3. Coagulation Phase: Formation of a fibrin clot through a series of reactions involving clotting factors that stabilize the platelet plug.

  4. Fibrolytic Phase: Breakdown of the clot after healing to restore normal blood flow.

Blood Agglutination Definition:

  • The clumping together of cells, particularly red blood cells, in response to an antigen-antibody reaction. Causes:

  • Occurs during blood transfusions if incompatible blood types are mixed, leading to an immune response. Importance:

  • Critical for blood typing and ensuring safe blood transfusions. If agglutination occurs, it can lead to serious complications, including hemolytic reactions.