Blood and Bloods Elements for Paramedic Students

Components of Blood

1. Plasma
   • Description: Plasma is the liquid component of blood, making up about 55% of its total volume.
   • Composition: It is primarily water (about 90-92%), but also contains proteins (like albumin, globulins, and fibrinogen), electrolytes (such as sodium, potassium, and calcium), nutrients (glucose, amino acids, and lipids), hormones, waste products (like urea and creatinine), and gases (oxygen and carbon dioxide).
   • Functions: Plasma transports nutrients, hormones, and proteins to the parts of the body that need it. It also helps in waste removal, blood clotting, and maintaining pH balance and body temperature.
2. Red Blood Cells (RBCs) or Erythrocytes
   • Description: RBCs are biconcave, disk-shaped cells that lack a nucleus.
   • Composition: They contain hemoglobin, a protein that binds oxygen and gives blood its red color.
   • Functions: The primary function of RBCs is to transport oxygen from the lungs to the tissues and carbon dioxide from the tissues to the lungs for exhalation.
3. White Blood Cells (WBCs) or Leukocytes
   • Description: WBCs are a diverse ( Many types of cell but Different from each other ) group of cells that are part of the immune system.
   • Types and Functions:
     • Neutrophils: Phagocytize bacteria and fungi; the most abundant type of WBC.
     • Lymphocytes: Include B cells (produce antibodies) and T cells (kill infected or cancerous cells).
     • Monocytes: Differentiate into macrophages and dendritic cells in tissues; phagocytize pathogens and dead cells.
     • Eosinophils: Combat multicellular parasites and certain infections; involved in allergic responses.
     • Basophils: Release histamine during allergic reactions and asthma.
4. Platelets or Thrombocytes
   • Description: Small, disk-shaped cell fragments without a nucleus.
   • Composition: Contain granules with clotting factors and other proteins.
   • Functions: Platelets play a critical role in blood clotting (hemostasis) by adhering to the lining of blood vessels, forming a plug at the site of injury, and releasing chemicals that promote clot formation.

Blood Functions

1. Transportation:
   • Oxygen and Carbon Dioxide: RBCs transport oxygen from the lungs to tissues and carbon dioxide from tissues to the lungs.
   • Nutrients: Blood carries nutrients like glucose, amino acids, and fatty acids to cells.
   • Waste Products: Blood removes waste products from metabolism, such as urea and carbon dioxide.
   • Hormones: Blood transports hormones from endocrine glands to target organs.
2. Regulation:
   • pH Balance: Blood helps maintain the pH of body fluids through buffers.
   • Body Temperature: Blood absorbs and distributes heat throughout the body.
   • Fluid Balance: Blood proteins and electrolytes help regulate fluid balance in tissues.
3. Protection:
   • Immune Response: WBCs defend against infections by identifying and destroying pathogens.
   • Clotting: Platelets and clotting factors in plasma prevent blood loss through clot formation.
   • Antibodies: Plasma contains antibodies that identify and neutralize foreign substances.

Blood Formation (Hematopoiesis)

• Location: Blood cells are produced in the bone marrow, particularly in the pelvis, sternum, and long bones.
• Process: Hematopoietic stem cells in the bone marrow differentiate into various blood cells (RBCs, WBCs, and platelets) through specific pathways regulated by growth factors and hormones.