tissues

Tissues• Tissue – aggregation of cells and noncellular

structures, which have similar structure, function and development

• General• 1. Epithelia• 2. Inner environment (blood and connective)• Special• 1. Muscular• 2. Nerve

Simple epithelia

Stratified epithelia:1. Stratified squamous nonkeratinized2. Stratified squamous keratinized3. Transitional (urothelium)

Endothelium Mezothelium

Simple cuboidal epithelium

Simple columnar epithelium

Stratified squamous nonkeratinized epithelium

Urothelium of urinary bladder

Urothelium of urethra

Glands

Glands

Goblet cells

Blood and hematopoiesis1. Blood compounds and functions

2. Plasma

3. Erythrocytes

4. Leucocytes

5. Theories of hematopoiesis

6. Stem cell structure and functions

7. Embryonic and postembryonic hematopoiesis

8. Classes of hematopoietic cells

9. Main features of different hematopoietic lines

Functions

• 1. Trophic

• 2. Respiration

• 3. Protection

• 4. Excretion

• 5. Homeostasis

• 6. Transport

Blood=cells + plasma (RBC+WBC+PL)

Leucocytes

Neutrophil

Eosinophil

Eosinophil

Basophil

Basophil

Lymphocyte

LymphocyteEchinocyte

Lymphocyte

Monocyte

Monocyte

Platelet

HEMATOPOIESIS –blood compounds development (blood cells

and plasma)

Hematocytopoiesis

Erythrocytopoiesis

Leucocytopoiesis

granulocytopoiesis

agranulocytopoiesis

Trombocytopoiesis

THEORIES OF HEMATOPOIESIS

• POLYPHYLETIC THEORY – each mature blood cell type is derived from its own distinct stem cell

• MONOPHYLETIC THEORY (A.A. Maximov) – there is one stem cell, which can form all the mature blood cells types.

• Multipotential stem cell (CFU-S – colony-forming-unit of spleen)

Hematopoietic stem cell

• 1. Appears in the yolk sac• 2. Thrives in RBM• 3. Similar to small dark lymphocyte• 4. Migrating cell• 5. Pluripotential cell (gives rise to different cells)• 6. Self-supporting cell• 7. Rarely dividing cell (Go)• 8. Sensitive cell

Differences between embryonic and

postembryonic hematopoiesis

Embryonic Postembryonic

Histogenesis of blood Blood physiologic regeneration

Extracorporal (extraembryonic)

Intracorporal

Intravascular Extravascular

Occurs in different organs RBM

Megaloblastic erythropoiesis mesoblastic

Normoblastic

CLASSES OF HEMATOPOIETIC CELLS

• I class – polipotent (pluripotent) stem cell.

• II class – hemistem cells for lymphocytopoiesis and myelopoiesis.

• III class – unipotent cell (committed) sensitive to exact hemopoietin (erythropoietin, leykopoietin, thrombopoietin).

• IV class – blasts (young actively dividing cells).• V class – maturing cells. • VI class – an “adult” mature cells in peripheral

blood.

1. Decrease in cell size (from 20 till 8 мm)2. Ejection (extrusion) of the nucleus3. Accumulation of hemoglobin in the cytoplasm4. Basophily decrease and acidophily increase

ERYTHROPOIESIS

GRANULOCYTOPOIESIS

GRANULOCYTOPOIESIS

• 1. Decrease in the cell size

• 2. Chromatin condensation

• 3. Changes in nuclear shape (flattening – indentation – lobulation).

• 4. Accumulation of cytoplasmic granules.

LYMPHOCYTOPOIESIS

LYMPHOCYTOPOIESIS

• 1. Begins in red bone marrow and then continues in lymphoid tissue.

• 2. Lifespan various in different types of lymphocytes.

• 3. Antigenindependent development – in the central hematopoietic organs (red bone marrow and thymus) and antigendependent – in peripheral ones (spleen, lymph nodes and nodules).

MONOCYTOPOIESIS

• 1. Decrease in cell diameter.

• 2. Decrease in nuclear diameter.

• 3. Cytoplasm basophily decreases.

• 4. Nucleus changes its shape from round to kidney-like

MONOCYTOPOIESIS

Megakaryocyte