Where do you find CT?
What are the fibers in CT?
What cells hang out in CT?
Connective Tissue
Holding it all together!
Connective tissue is found
everywhere!
Main types:
1. Connective tissue proper –
We will focus on this one most of next week!
2. Cartilage
3. Bone
4. Blood
Properties
1. common origin Mesenchyme
Mesenchyme is an embryonic tissue
From the mesoderm
Ectoderm
Endoderm
2. degrees of vascularity
3. great degree of “non-living” extracellular
matrix
What do we mean non-living?
Connective Tissue – essential functions
1.
2.
3.
4.
5.
Binds structures
Provides support and protection
Insulation
Transportation
Energy storage
Structural elements:
1. Ground substance (matrix)
2. Fibers
3. Cells
Wide range of varying tissue!
Different structuresdifferent functions!
Ground Substance (matrix)
Unstructured material
Fills spaces/contains fibers
Composed of:
1. interstitial fluid
2. cell adhesion proteins glue like function
3. Proteoglycansprotein core (point of
attachment) “GAGs” glycosaminoglycans
1. (interlock trapping water)
Major Cell Types: Blasts vs. Cytes
 Fibroblasts- cells that produce fibers by
secreting proteins into the matrix of CT tissue
 Macrophages- originate as WBCs specialized
cell phagocytosis
 Mast Cells- release heparin prevents blood
clotting, release histaminepromotes reactions
associated with inflammation and
allergies.
Fibroblast—laying matrix
CONNECTIVE TISSUE-3 FIBER
TYPES
A. Collagenous fibers- Thick threads of
protein (collagen)
Grouped in long parallel bundles, they are
flexible, but only slightly elastic.
Great tensile strength (ligaments and
tendons)
B. Elastic fibersComposed of protein elastin
These fibers branch, forming complex
networks.
weaker than collagenous fiber
however they stretch and can return back to
there shape
Elastic Fibers
C. Reticular Fibers
Very thin collagenous fibers
Highly branched, form supporting
networks
(LIKE A NET)
Reticular Fibers
When it comes to CT you can have a
variety of types….
Loose CT
1. areolar tissue
2. Reticular tissue
3. Adipose tissue
Dense
Regular
Irregular
Cartilage types
I.
Loose Connective Tissue
Forms delicate thin membranes
throughout the body
Main cellFibroblasts separated by a gellike matrix
Binds skin to underlying organs and fills
spaces between muscles
Lies beneath epithelium
2
Adipose Tissue
FAT, develop when certain cells
store fat in droplets within their
cytoplasm.
Beneath the skin, stored in many
other locations as well.
Cushions, insulates, stores energy.
3
 Dense Connective Tissueregular or irregular
 Closely packed, thick, collagenous fibers and a
close network of elastic fibers. Relatively few
cellsmost of which are fibroblasts.
 VERY STRONG TISSUE
4
 Cartilage
 Rigid CTprovides support, frameworks, and
attachments, protects underlying tissue
 forms structural models for developing bone.
 Cartilage matrixabundant, largely composed
of colagenous fibers embedded in a gel-like
ground substance .
Cartilagea special case
SPECIAL CARTILAGE CELLS
CHONDROCYTES, occupy small
chambers called lacunae
Cartilage structures are enclosed in a
covering of CTperichondrium (contains
the blood vessels that deliver nutrients)
THE INTERCELLULAR MATRIX
DISTINGUISHES THE TYPE OF
CARTILAGE! 
Hyaline Cartilage
*most common type
*very fine collagenous fibers
(looks like white glass)
Location: end of bones, joints, soft part of
nose, trachea
Elastic Cartilage
Dense network of elastic fibers
Much more flexible than hyaline cartilage
Location: framework of ear, parts of larynx
Fibrocartilage
Tough tissue, contains many collagenous
fibers
-shock absorber for structures subjected to
pressure.
Location: vertebrae (discs), knees, pelvic
girdle.