DV

BLOOD part I.pdf

Page 1: Blood Components and Cell Types

  • Erythrocytes (Red Blood Cells)

    • Important for oxygen transport.

    • Variants include:

      • Hypochromic Macrocytes

      • Microcytic Cells

      • Normoblasts

      • Spherocytes, Stomatocytes, Target Red Cells, Teardrop Red Cells

      • Elliptocytes (Ovalocytes)

      • Schizocytes (Schistocytes)

      • Sickle Cells, Acanthocytes, Echinocytes

      • Bite Cells, Howell-Jolly Bodies, Basophilic Stippling

Page 2: What is Blood?

  • Definition: Blood is a connective tissue.

  • Composition:

    • ~42% fluid matrix (plasma)

    • ~58% cellular components

    • About 7% of total body weight (~4-5 liters in adults)

  • Components composition:

    • Plasma: ~58%

    • Platelets: <1%

    • White blood cells: ~1%

    • Red blood cells: ~42%

Page 3: Plasma Composition

  • Plasma: Fluid component of blood, created via absorption of water and salts from the gastrointestinal tract.

  • Composition:

    • 92% Water

    • 7% Proteins (mainly synthesized by liver):

      • Albumin (60%): Essential for maintaining colloid osmotic pressure.

      • Globulins (Immunoglobulins)

      • Fibrinogen: Crucial for blood clotting

      • Transferrin: Iron transport.

    • 1% Amino Acids, Glucose, Lipids, Ions, Vitamins, O2, CO2

Page 4: Cellular Components of Blood

  • Red Blood Cells (Erythrocytes): Transport oxygen.

  • White Blood Cells (Leukocytes): Immune response mediators.

  • Platelets (Thrombocytes): Crucial for clot formation.

  • Notably, leukocytes are the only fully functional cells in blood circulation.

Page 5: Function of Blood Cells

  • Red Blood Cells (RBCs): Transport O2 and CO2.

  • White Blood Cells: Mediate immune responses.

  • Platelets: Involved in blood clotting.

  • Cell Counts:

    • RBCs: ~5 x 10^6/µl

    • WBCs: ~4-11 x 10^3/µl

    • Platelets: ~1.5-4.5 x 10^5/µl

  • Specialized immune cells include mast cells and macrophages.

Page 6: Blood Cell Development

  • Hematopoiesis: The production of new blood cells.

    • Prenatal Hematopoiesis: Occurs in an embryo where stem cells migrate to develop into various blood cells.

Page 7: Postnatal Hematopoiesis

  • Begins after birth.

  • Active Hematopoiesis Locations:

    • Bone marrow in all bones until approximately 5 years old,

    • After 5, active sites decline, concentrating in pelvis, spine, ribs, cranium, and the proximal ends of long bones.

    • Yellow fat marrow can be activated for hematopoiesis when needed.

Page 8: Immune Cell Development

  • Hematopoietic Lineage:

    • Pluripotential stem cells: Uncommitted stem cells found in bone marrow.

    • Capable of self-renewal and differentiation into multiple cell types.

Page 9: Bone Marrow and Blood Cell Lifespan

  • Red marrow in spongy bone produces blood cells.

  • Lifespans:

    • RBCs: 120 days

    • Neutrophils: ~6 hours

    • Lymphocytes: 200 days

    • Granulocytes: 9-13 days

    • Platelets: 9-12 days

Page 10: Hematopoiesis Regulation

  • Cytokines: Proteins regulating hematopoiesis.

  • Key growth factors and target cells outlined, including:

    • Erythropoietin (EPO)

    • Interleukins

    • Colony Stimulating Factors

Page 11: Erythropoiesis

  • Erythropoietin (EPO): Secreted glycoprotein from kidneys that stimulates RBC production.

  • Regulation: Increased EPO production occurs in response to decreased oxygen levels (hypoxia).

Page 12: Discussion

  • Engages viewers in interactive content related to blood and hematopoiesis.

Page 13: RBC Generation Process

  • Erythroblasts develop into reticulocytes and finally mature RBCs in the blood stream.

  • Maturation involves reduction in size, loss of organelles, increase of hemoglobin, and enucleation.

Page 14: Red Blood Cell Characteristics

  • RBCs are abundant and specialized for gas transport.

  • Lack organelles to maximize hemoglobin capacity and increase diffusion efficiency.

  • Lifespan of ~120 days where they rely on glycolysis for ATP production.

Page 15: RBC Flexibility

  • RBCs must navigate small capillaries and withstand mechanical forces while maintaining their shape.

  • Membrane structure and cytoskeletal organization allows for adaptability in varying osmotic conditions.

Page 16: Hemoglobin Structure

  • Hemoglobin is a globular protein with subunits, vital for oxygen transport.

  • Composition includes heme groups responsible for binding O2.

  • Types: Deoxyhemoglobin (without O2) and Oxyhemoglobin (bound to O2).

Page 17: Oxygen Transport by Hemoglobin

  • Majority of blood oxygen is carried by hemoglobin.

  • Binding and release of O2 are reversible processes influenced by blood conditions.

Page 18: Blood Test Indices

  • Blood Test Parameters:

    • Absolute RBC count

    • Hb levels

    • Hematocrit (Hct)

    • Mean Corpuscular Volume (MCV)

    • Mean Corpuscular Hemoglobin (MCH)

    • MCH Concentration (MCHC)

    • Red Cell Distribution Width (RDW)

  • Reference Values: Ranges provided for males and females.

Page 19: Discussion

  • Interactive engagement related to blood indices and tests.

Page 20: Iron's Role in RBC Production

  • Iron is critical for hemoglobin function and oxygen transport.

  • Overview of iron transport and storage proteins, including DMT1, Transferrin, Ferritin.

  • Caution about iron toxicity from excess consumption.

Page 21: Discussion

  • Engages participants in further discussions on iron and RBCs.