Introduction (from your book)
Connective tissues bind structures, provide support and protection, serve as frameworks, fill spaces, store fat, produce blood cells, protect against infections, and help repair tissue damage. Connective tissue cells are usually farther apart than epithelial cells, and they have an abundance of intercellular material, or matrix, between them.
There are many different types of connective tissue - we'll start easy and move to the more difficult.
Blood - Most all the cells you see in this picture are are red blood cells (erythrocytes), and the blue and green arrows are pointing to white blood cells (leukocytes). The matrix material, know as plasma in blood, can not be seen because it does not stain. Blood is a good example of showing the distance between cells that is often associated with connective tissues.
Where can you find blood in your body? What organ system contains blood?
Bone (specifically "compact bone") Bone has a very specific look - it looks like a series of circles. The green arrows are pointing to areas of the bone tissue where you can find individual bone cells (osteocytes).
Cartilage - specifically Hyaline Cartilage
The green arrow is pointing to matrix material and the blue dots are the cells (chondrocytes).
Tendon (Generic name: regular dense fibrous connective tissue).
Lots of collegen fibers and elastin fibers can be found in tendons - notice how all the lines in the picture are in one direction (up and down in this case) -since all the fibers are running in one direction the tendon is very strong in one direction.
Adipose Tissue (Green Arrow) - also know as fat tissue.
Fat does not stain well and so fat cells will look "empty" -but they are actually full of lipids.
FYI: The black arrow is pointing to an artery and the red arrow is pointing to a vein.
Collegen (green arrow)
Collegen is a very strong protein fiber. Here the collegen fibers are stained blue and are running in many different directions (as compared to tendons). When the collegen is arranged in this manor, the tissue will be strong in several dirctions. This collegein is found just under your skin and helps hold it to the bones. When humans age, their collegen quantities decrease and the skin sags.
Collegen is NOT a tissue, but is a protein commonly associated with connective tissues.
Elastin (green arrow)
Elastin is a protein commonly associated with connective tissues. This image is of an aorta, a very high pressure blood vessel. The elastin in the aorta enables it to contain blood that is under a large quantity of pressure without exploding.
GO BACK TO THE FIRST PAGE (The GC 1135 Histology Page)