5. CONNECTIVE TISSUE
Function
1- Structural support
2- Metabolic function
3- Defensive function
4- Tissue repair
5- Special function as energy storage in adipose tissue, blood cell
formation
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10. CONNECTIVE TISSUE
CT Ground substance(Matrix):
May be
Liquid as in Blood
Gelatinous like areolar CT
Rubbery as in Cartilage
Hard as in Bone
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12. CONNECTIVE TISSUE
Fixed cells are relatively stable
Include: ( ME-RE-PER-END, 4F)
1. Mesenchymal cells
It is called Embryonic stem cell, remains undifferentiated in
adult CT
Light Microscopy (L/M) small cell with long cytoplasmic
processes, fainty basophilic cytoplasm
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13. CONNECTIVE TISSUE
Fixed cells are relatively stable
Include: ( ME-RE-PER-END, 4F)
1. Mesenchymal cells
Elecron Microscopy (E/M) (cell making protein)
Cytoplasm contains Golgi apparatus, rough endoplasmic reticulum,
mitochondria, ribosomes
Function: Stem cell for most of CT cells.
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16. CONNECTIVE TISSUE
Fixed cells are relatively stable
Include: ( ME-RE-PER-END, 4F)
Fibroblast : is the most common cell in the CT
LM: fusiform or stellate with long process cell, pale stained
nucleus with Basophilic cytoplasm
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17. CONNECTIVE TISSUE
Fixed cells are relatively stable
Include: ( ME-RE-PER-END, 4F)
Fibroblast : is the most common cell in the CT
EM: Euchromatic Nucleus, prominent nucleolus
Cytoplasm has the protein secreting organelles (Golgi
apperatus, rough endoplasmic reticulum,
mitochondria, ribosomes)
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18. CONNECTIVE TISSUE
Fixed cells are relatively stable
Include: ( ME-RE-PER-END, 4F)
Fibroblast : is the most common cell in the CT
Function:
Growth, repair of the CT
Synthesis,secretion, maintains the extracellular matrix as fibers and ground
substance.
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20. CONNECTIVE TISSUE
Fibrocytes
It is considered as inactive form of the fibroblast
LM: small fusiform , deep basophilic nucleus,
acidophilic cytoplasm
EM: the cytoplasm contains few organelles
FUNCTION: tissue repair
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27. CONNECTIVE TISSUE
Endothelial cells
EM: the cytoplasm contains few organelles
FUNCTION:
o facilitate the exchange of the substances across the
vascular wall,
o Produce type 4 collagen fibers.
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29. CONNECTIVE TISSUE
Pericytes
It is partially surrounds the endothelial cells of capillaries and
small venules
It is a perivascular cell with multifunctions .
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31. CONNECTIVE TISSUE
Pericytes
EM: the cytoplasm contains myofilaments
FUNCTION: It can be differentiate into
Fibroblast in healing ,
Macrophage if needed,
Smooth muscle during the development of the new blood vessels.
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33. CONNECTIVE TISSUE
Adipose cell
There are two types
A.Unilocular adipose cell
B.Multilocular adipose cell
Function:
Storage and release of fat
Plays an important role in energy homeostasis
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34. CONNECTIVE TISSUE
LM:
Shape : Large spherical cell
Nucleus : flat and displaced , cytoplasm shows a single lipid droplet
in a signet ring appearance
Special stain: Sudan Black, osmium tetraoxide black
EM: the cytoplasm contains few organelles
Unilocular Adipose cell
It forms the white adipose tissue
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35. CONNECTIVE TISSUE
Multilocular adipose cell
It forms the brown adipose tissue
LM:
Shape : small polygonal cell
Nucleus : eccentric rounded nucleus
Cytoplasm: strongly acidophilic in H&E stain.
EM: the cytoplasm contains mitochondria, smooth endoplasmic
reticulum.
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37. CONNECTIVE TISSUE
Fixed macrophages
Originate from the blood monocytes
Types:
A. Fixed macrophages setteled in CT
B. Free macrophages travel between Ct and Blood
Macrophages are distributed in most organs and tissues and form
mononuclear phagocytic system
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