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.