Connective tissue is a basic type of tissue that provides structural and metabolic support. It originates from mesenchyme and is composed of widely separated cells in an extracellular matrix. Connective tissue functions include binding, supporting, protecting, immune protection, storage, and transport. There are two main types - loose connective tissue which contains abundant ground substance and fewer fibers, and dense connective tissue which contains tightly packed fibers. Loose connective tissue is found in subcutaneous tissue and around blood vessels and organs. The main cell types include fibroblasts, macrophages, mast cells, plasma cells, adipocytes, and wandering blood cells.
3. Tissues are groups of cells that are
similar in structure and function.
* Epithelium * Muscle
Coverings Movement
Linings of surfaces
* Connective * Nervous
Support Control
Bone, ligaments, fat Brain, nerves, spinal
cord
4. Connective Tissue
It is a basic type of tissue, of
mesodermal origin,
Which provides structural
and metabolic support for
tissues and organs.
5. GENERAL CHARACTERISTICS
1- are formed of widely separated, few cells
with abundant extracellular matrix.
2- Originate from mesenchyme ( an
embryonic tissue ) which develops mainly
from mesoderm.
3- most C.T. are vascular.
19. Loose connective tissue
• Contains abundant ground substance
and tissue fluid, nearly all type of C.T.
cells and less amounts of fibers.
• Located in subcutaneous tissue, lamina
propria of gastrointestinal & respiratory
tracts, around blood vessels & organs
and under serous membranes.
• In inflammatory condition it swells
because of increased extra-cellular fluid
(Edema).
24. Collagen synthesis
•• polyribosomes
polyribosomes
polypeptide chain
polypeptide chain
•• rER & GA modified
rER & GA modified
procollagen Vit C
procollagen
•• Exocytosis
Exocytosis
•• Converted by enzyme
Converted by enzyme
•• Tropocollagen or
Tropocollagen or
collagen molecule
collagen molecule
•• Align to form the final
Align to form the final
collagen fibrils
collagen fibrils
26. Type of collagen fibers
On the basis of the combination of α chains they contain.
Type I* :- loose connective tissue , dermis
tendon , fibrocartilage & bone
Type II* :- cartilage & nucleus pulposus
Type III* :- slender fiber form network,
reticular fiber
Type IV :- basement membrane
Type V & X :- perilacunar of cartilage
28. Reticular Fibers
•Thin collagen fibers arranged in
framework instead of bundles.
•Synthesized by the fibroblasts.
•They form the reticular network of
some organs such as lymph nodes
and bone marrow.
•They present also in basement
membrane.
29.
30.
31.
32. Elastic fibers (yellow fiber)
•Slender, long and branching fibers in loose
connective tissue, but coarse bundles in
elastic ligaments.
•Formed by the fibroblasts and smooth
muscle cells.
•Composed of protein elsatin and can be
stretched to one and half times its original
length.
•It is present in large arteries, larynx and
trachea, ligamentum flavum and framework
of the spleen.
33.
34. Macrophage
• They may be fixed or transient.
• They are active phagocytes removing cell
debris and protecting the body against
foreign invaders.
• They are derived from monocytes
(transient) or from UDMC (histiocytes).
• Highly motile, irregular in shape with
pseudopodia.
• Have dark nucleus and basophilic
cytoplasm containing numerous
lysosomes, vacuoles and residual
bodies.
41. Plasma cell
• They are derived from B-lymphocytes.
• Large ovoid cells with eccentrically placed
nucleus.
• Its cytoplasm is intensely basophilic
(RER).
• Its nucleus has the characteristic “clock-
face” or “radial spoke” appearance.
• They present in areas of chronic
inflammation and foreign bodies, where
they manufacture and secrete antibodies.
45. Fat / Adipose
Cell in adipocytes.
• Loose C.T. very rich
• Two types of adipose C.T.
• Unilocular (white fat) C.T.: its fat
cells are of unilocular type, present
in subcutaneous tissue, around
organs and blood vessels.
• Multilocular (brown fat) C.T.,
present in infants and hibernating
animals, cells are rich in
mitochondria, supply heat.
46. Fat / Adipose Cell
Brown adipose tissue
White adipose tissue
47.
48. Dense irregular
• Contains abundant amounts of fibers
with less cells and ground substances.
• Has tightly packed coarse collagen
bundles arranged randomly in all
directions, with few elastic fibers.
• Fibroblasts and other less cells are
arranged between the collagen fibers.
• They are found in dermis of skin,
capsule of organs, sheaths around
nerves and dura mater.
51. Dense regular
• Contains abundant amounts of fibers with
less cells and ground substances.
• Has tightly packed coarse collagen
bundles arranged in parallel fashion to
form cord-like cylinders (tendons &
ligaments) or sheets (aponeurosis).
• Fibroblasts are arranged between the
collagen fibers so they appears elongated
with their dash-like elongated nuclei.
• It is also called white fibrous C.T.
53. Cell types Main product or Main function
activity
Fibroblast Production of fibers and Structural
ground subst.
Plasma cell Production of antibody Immunologic
Lymphocyte Production of Immunologic
immunocompetent cell
Eosinophil Phagocytosis of Ag-Ab Immunologic
complex
Macrophage Phagocytosis of foreign Defense
& Neutrophil subst. & bacteria
Mast cell & Liberation of histamine Defense
Basophil
Adipose Storage of neutral fat, Energy reservior;
heat production heat production