The Haemopoietic System and Blood Properties

Haemopoietic System

• This system involves blood and blood-related components
• Erythropoiesis is an example

Blood

• Connective tissue in fluid form
• It consists of blood cells and plasma.
• Blood cells include:
  • Red blood cells (RBCs or erythrocytes)
  • White blood cells (WBCs or leucocytes)
  • Platelets (thrombocytes)

Plasma

• Plasma without clotting factors is called serum
• Consists of:
  • 90-92% water
  • 6-8% proteins
• Proteins include:
  • Fibrinogen (for blood clotting)
  • Globulin (for defense)
  • Albumin (for osmotic balance)

Properties of Blood

• Colour varies:
  • Arterial blood is scarlet red
  • Venous blood is purple red
• Volume:
  • 5 liters in males
  • 4.5 liters in females
  • 450 ml in newborns
• Reaction and pH is slightly alkaline, around 7.4
• Specific gravity of total blood ranges from 1.052 to 1.061
• Viscosity is approximately 5 times more viscous than water

Functions of Blood

• Nutritive function: transports glucose, amino acids, lipids, and vitamins to different body parts
• Respiratory function: transports oxygen from alveoli to tissues and carbon dioxide from tissues to alveoli
• Excretory function: transports waste products formed in tissues during metabolic activities
• Transport of hormones and enzymes: hormones secreted by ductless glands are released directly into the blood
• Regulation of water balance, helping maintain water content
• Regulation of body temperature via thermoregulation due to its high specific heat, where heat gain equals heat loss
• Regulation of acid-base balance: plasma proteins and hemoglobin act as buffers
• Storage function: stores substances like proteins, glucose, sodium, and potassium, releasing them when needed
• Defense function: WBCs provide a defensive function

Red Blood Cells (RBCs)

• Non-nucleated, except in camels
• Count: 4-5.5 million per cubic mm, 5 million in males
• Morphology:
  • Biconcave, disc, and dumbbell shaped
  • Thin in the center
  • Thick at the periphery

White Blood Cells (WBCs)

• Nucleus present
• Granules may or may not be present
• Classification:
  • Granulocytes: neutrophils, basophils, eosinophils
  • Agranulocytes: monocytes, lymphocytes

WBC Morphology

• Neutrophils are multi-lobed
  • 2-5 lobes present.
  • Cytoplasm stains with both eosin and methylene blue
  • Indicates purple color in the cytoplasm
• Eosinophils are bilobed and stained by eosin
  • Red-colored cytoplasm
• Basophils are bilobed and stained by methylene blue
  • Blue-colored cytoplasm
• Monocytes have a large, kidney-shaped nucleus without granules, located peripherally or centrally
• Lymphocytes have a bean or oval-shaped nucleus covering the cell, without granules
• WBC count: Diameter & Life span (days): Percentage
  • Neutrophils: 10-12μm, 2-5 days, 50-70%
  • Eosinophils: 10-14μm, 1-12 days, 2-4%
  • Basophils: 8-10μm, 1. 12-15 days, 0-1%
  • Monocytes: 14-18μm, 2-5 days, 2-6%
  • Lymphocytes: 7-12μm, 1/2-1 day, 20-30%
• Total leukocyte count (TLC) is 4-11 thousands/mm³
• WBCs exhibit diapedesis, squeezing through capillaries

WBC Properties

• Exhibit amoeboid movement
• Haemotaxis- Chemotaxis

WBC Functions

• Defense mechanism: neutrophils defend against foreign particles
• Platelet activation: secreted platelets activating factors for platelet aggregation during injury
• Eosinophils: defense against parasites, increase during allergic conditions
• Detoxification of foreign protein
• Basophils: play a role in healing processes and acute hypersensitivity reactions
• Monocytes: phagocytic and defensive in nature
• Lymphocytes: provide immunity
  • T-lymphocytes: cell-mediated immunity
  • B-lymphocytes: humoral immunity

Thrombocytes (Platelets)

• Non-nucleated
• Diameter: 2.5 μm
• Volume: 7.5 cubic μm
• Spherical or rod-shaped
• Transform into a disk or oval shape when inactivated
• Count: 2.5 lac/mm³
• Range: 2-4 lac/mm³

Thrombocytes Properties

• Adhesion: the property of sticking to a rough surface
• Aggregation: grouping of platelets after adhesion
• Agglutination: coagulation/clumping together of platelets, forming a clot

Thrombocytes Functions

• Role in blood clotting - formation of intrinsic prothrombin activator
• Role in clot retraction: involves actin, myosin, and thrombostenin for clot contraction and size reduction
• Prevention of blood loss (Hemostasis): Platelets have 5-HT, causing blood vessel constriction
• Repair of ruptured blood vessels
• Role is defense mechanism

Lifespan & Variations

• Lifespan: 10 days
• Range: 8-11 days

Physiological & Pathological Variation: Cell Creation

• Pluripotent Haemopoietic Stem Cells
• Lymphoid Stem Cell
• Erythropoiesis process of origin, development, and maturation of blood erythrocytes

Erythropoiesis Sites

• Before birth:
  • Mesoblastic stage in the first 2 months of intrauterine life
  • Formed from the mesenchyme of the yolk sac
  • Hepatic stage from the 3rd month of intrauterine life
  • The liver is the main RBC producing site, along with the spleen and lymphoid organs
  • Myeloid stage in the last 3 months, involving bone marrow and the liver
• After birth:
• Up to 20 years of age, RBCs are produced from the red bone marrow of all bones, especially long and flat bones
• After 20 years, RBCs are produced from membranous bones like the vertebrae, sternum, ribs, scapula, iliac and skull bones, and the ends of long bones

Stages of Erythropoiesis

• CFU-E cells transform into:
  • Proerythroblast
  • Early normoblast
  • Intermediate normoblast
  • Late normoblast
  • Reticulocyte
  • Mature erythrocyte
  • Proerythroblast
    • First cell derived from CFU-E
    • Diameter : 20μm
    • Nucleus is large and occupies the whole cell
    • Does not contain haemoglobin
    • But synthesis of haemoglobin is started here, but seen in intermediate normoblast.
    • Cytoplasm is basophilic in nature
• Early normoblast, Small than proerythroblast
  • Diameter: 15 μm
  • The nucleoli disappear
    • Cytoplasm is basophilic erythroblast
    • Condensation of chromatin network
  • Intermediate Normoblast Smaller is a normoblast
    • Diameter: 10.12 ym
    • Haemoglobin starts appearing
    • Nucleus is present
    • Condensation occus further
    • Give a polychromatic
• Late Normoblast Diameter is 8 to 10 ym
• At starting nucleu becomes very small and very much condensed chromation network
• Quantity of hermoglobin increases and cytoplasm becomes acidophilio so the cell is K/s

Reticulocyte Immature Red Blood Cell Due of disintegrated Matured erythrocyte Reticulocytes network appear Having cave shape

Factors Responsible for Erythropoiesis

• Physiological variations in RBC include:
• Increase in RBC count: polycythemia- Increased RBC Volume

Age Factors

• At birth Rbc count is 8-10 millionImm Sex

Female and male some count of Red Blood Cells

High altitude levels

Hypoxia-kidney and Borie levels Sycete -Enythroporitin

Volume factors

Muscular- Muscular exercise Hypoxia- sympathetic

• Sympathetic activity released releases are activity

• Emotional condition a and exercise

• High temperature environments RCD volumes

• B decrease class Anemia

• High barometic pressure -Deep Sea

• Sleep activity

• pregnancy

Pathological variations: Cell creation

primary polycythemia A plastic Disse- RBC volumes

Types of Polycythemia

Secondary and some conditions

Respitary disorders Chronic (CO Poisoning)

• Phosphorus and arsenic count

Anemia factors

• Venos blood size

RBC Size in

Microcytes

Irdam anemias

• Prolonged Forced

Increased cosmotic pressure

Marrocytes

Megol ablastic anomias Decreased Cosmatic pressure

Factors in RBC shape with Anemia

Anisotytes

Occurs in perritious a nemici

Crenation

shurinkage

Hypertomic conditions

Pherocyotosis

Hypotonic and

Hypertomic condition

• Elliptocytes

In certain shapes is

• Sickle cell - anemia
• Crescenting shape Sickle cell

Potilocytosis

• Membrane shaped

puntuale basophilism

Stratiod appearance

Striated

Tireside materials

RBC Structure variations

• Leads poisuring

• Rings or twisted stands

• Gables

HOWELL

• BOD/Es"

Lenkaporisin

• Plari polent Hemopoilic

Plasty -

colony

• Myloblast
• Blaral
• Monocle

Promy elolyte # Promocytes

• Neteiphall
• Osiophil

E - Meter

Basophil

B *meter cyte

hemopriph

Heralds and

• Hemopriph

Hemes -

Factors for

• Jeen

Forms of

types of

A - adull

Fetal HOB

High affinity

Note

• Fetal volume

Dissociation

• Dissociation Curvof shift of lefl-

Heamoglobin

• RBC Matter to

• RBC-36%

Hormonal contents

• RCD- 95% and 34% to west Weight

Normol hermegoblobin contents

12-14- and 16g10t

types of Aoe

• Sex factor Rbc is destroyed
• RBC Split

Hema d

• Irion stored"
• U- Reutired synthesies Synthise B and Bile