LECTURE THREE
JENAN M .M S.C.
Connective Tissue
Connective T: Is the most diverse of the four tissue types with wide variety of
function . forms (CT) can be considered as a glue that holds the body together. All (CT)
has three main components, cells, fibers and extracellular matrix all immersed in the
body fluid
 Functions of Connective Tissue.:
Storage of energy
Protection of organs
Provision of structural framework for the body
Connection of body tissues
Connection of epithelial tissues to muscle tissues
 Cells of the Connective Tissue.: There are three main cells types in connective T.
 Fibroblasts: these important cells are the ones that lay down the extracellular matrix
 Macrophages: these cells are large and are derived from blood cell
 Mast cells: these cells communicate chemically with our blood.
Other cells that may find in specific connective tissues are:
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Osteocytes-- only found in bone
Chondrocytes-- only found in cartilage (or developing bone)
Adipocytes-- only found in adipose tissue for storing fat
Blood cells-- found only in blood (unless you are injured) and there are many types of
blood cells.
 Reticulocytes-- found only in reticular connective tissue.
 Fiber Of Connective Tissue :
 Collagen Fibers : large fibers made of the protein collagen and are typically the most
abundant fibers . promote tissue flexibility.
 Elastic Fibers : intermediate fibers made of the protein elastin . branching fibers that
allow for stretch and recoil
 Reticular Fibers : small delicate, branched fibers that have same chemical composition
of collagen.
LECTURE THREE
JENAN M .M S.C.
 Types of Connective Tissue :
1. True Connective T.
a- Loose C T.
2. Support Connective T.
a- cartilage
b- Dense CT.
b- Bone
3. Liquid Connective T.( Blood )
1. True connective tissue : is classified depending on the amount, type, arrangement,
abundance of cells, fibers and ground substance into:
A-Loose connective tissue
B-Dense connective tissue
A- Loose connective tissue: is a very common type of CT. that supports many
structures .it's usually supports epithelialT, , has the main components of CT( cells, fibers
and ground substance )
1. Areolar CT.: consists of all three types of fibers, several types of cells, and
semi-fluid ground substance
found in: subcutaneous layer ,mucous membranes, around blood vessels, nerves and
organs , function : strength , support and elasticity
2. AdiposeT.: consists of adipocytes; appearing fat cells. They store energy in
the form of triglycerides (lipids).
found in: subcutaneous layer, around organs and in the yellow marrow of long bones
function : supports, protects, serves as an energy reserve .hypodermis, within abdomen
and breasts
3. Reticular CT.: consists of reticular fibers and reticular cells , found in : liver ,
spleen ,and lymph nodes .
function : forms the framework ( stroma) of organs and binds together smooth muscle
tissue cells.
B- Dense Connective Tissue:
Dense regular connective tissue .
Dense irregular connective tissue.
1.Denese regular Connective Tissue.:
 consists of bundles of collagen fibers and fibroblasts.
LECTURE THREE
JENAN M .M S.C.
 found in: tendons , ligament .
 function : provide strong attachment between various structures.
2. Denese Irrgular Connective Tissue.:
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consists of randomly-arranged collagen fibers and a few fibroblasts.
Found in: fasciae, dermis of skin, and heart valves.
Function : provide strength . dermis of skin, submucosa of digestive tract.