Blood Composition and Functions

Blood Composition

• Blood is composed of plasma (approximately 60%) and formed elements (approximately 40%).
• Plasma is primarily water, with dissolved proteins, electrolytes, nutrients, and waste products.
• Formed elements include red blood cells (erythrocytes), white blood cells (leukocytes), and platelets (thrombocytes).

Importance of Albumin

• Albumin is a vital protein synthesized in the liver. Its role is crucial in regulating blood's colloid osmotic pressure.
• It plays a key role in transporting various substances, including fatty acids, cholesterol, lipoproteins, bilirubin, calcium, steroids, hormones, amino acids, and drugs.

Blood Characteristics

• Blood's pH is around 7.4.
• Its density is approximately twice that of water.
• Hematocrit, the percentage of red blood cells (RBCs) in the blood, can vary depending on factors.

Red Blood Cells (RBCs)

• RBCs are differentiated from progenitor cells in bone marrow, undergoing several stages before maturity.
• They are responsible for oxygen transport through hemoglobin, reaching a 34% concentration.
• Reticulocytes, an immature form of RBCs, are found in the blood, with a concentration of slightly less than 1% among mature RBCs.
• Production of Erythropoietin (EPO) is primarily made in the kidneys.

Blood Ion

• Ions such as carbonate are vital regulators in blood acid-base balance and CO2 transfer.

Inflammation & Immunity

• Inflammation is a critical body response to tissue damage or infection.
• Neutrophils and macrophages play crucial roles in phagocytosis and tissue repair during inflammation.
• Leukocytes are a critical component of the body's defense mechanism against infection.
• Monocytes are differentiated into macrophages, vital components in tissue-level phagocytosis.
• The chemotactic process is important in attracting immune cells to the injured area.
• The Monocyte-Macrophage Cell System is important in the lungs to eliminate foreign particles and debris.

Immune System Components

• The thymus is a primary lymphoid organ responsible for T cell maturation.
• The spleen is a secondary lymphoid organ playing a role in filtering blood.

Immune System Function

• The innate immune system is a quick, non-specific response to infection.
• Acquired immunity is a slow, specific response including humoral (antibody-mediated) and cellular (cell-mediated) responses.

Blood and Hemostasis

-Hemostasis involves several mechanisms to stop bleeding when a blood vessel is injured.

• The intrinsic and extrinsic pathways are engaged in blood clotting to form a blood clot.
• Clots are stabilized by fibrin-stabilizing factor.
• Clotting occurs via the cascade of chemical reactions after thrombin is formed.

Pulmonary Ventilation

• Pulmonary ventilation includes inhalation (inflow of air) and exhalation (outflow of air).
• Four major functions of respiration are: pulmonary ventilation, diffusion of gases (oxygen and carbon dioxide), oxygen and carbon dioxide transport, and regulation.
• The muscles involved in pulmonary ventilation include the external intercostals, sternocleidomastoid, anterior serrates, scaleni, and the diaphragm.
• Elastic forces of the lungs include lung tissue which tend to collapse, and surface tension due to fluid lining the alveolar walls

Gas Exchange

• Gas exchange happens between the air in the alveoli and the blood in capillaries through diffusion.
• Gas exchange also occurs in body tissues through diffusion from capillaries to the tissues.

Blood Vessels

• Blood Vessels, including Arteries, Arterioles, Capillaries, Venules, and Veins have specific roles in transportation- including maintaining adequate pressure among other functions.
• Arterioles have a critical function in regulating blood flow to different tissues.
• Capillaries are the sites for exchange of gases and other substances between blood and tissues.
• Pulse pressure is a critical measure in assessing blood flow.
• Blood pressure is regulated by various mechanisms involving nerves, hormones, and other factors.
• Systemic circulation and pulmonary circulation are crucial for blood flow throughout the body.

Hemostasis

• Hemostasis is the process to stop bleeding. Factors include the immediate vascular constriction, platelet aggregation (formation of a platelet plug), and activation of the clotting cascade (formation of a blood clot).
• The formed clot contracts by activating platelet thrombosthenin, then actin and myosin molecules.
• Clot retraction involves the process to contract the edges of the broken-down blood vessel to help with hemostasis.

Microcirculation

• Microcirculation occurs at the level of Capillaries within tissues.

Lymphatic System

• The lymphatic system plays a role in fluid balance and immune functions.
• Tissue fluid and interstitial fluid are critical components that affect pressure.

Electrocardiogram (EKG)

• An EKG interprets the electrical activity of the heart.
• Typical components of an electrocardiogram include several waves and segments representing the different stages of the cardiac cycle.

Explore the essential components and characteristics of blood, including plasma, formed elements, and the crucial role of albumin. This quiz delves into the functions of red blood cells and how they contribute to overall health. Test your knowledge on blood's composition and its physiological significance.