Lab 3 - Connective Tissue Flashcards
5 common characteristics of CT
-there are no free surfaces, CT fills spaces with a mixture of cells and extracellular material
-CT underlies epithelia and surrounds muscle and nervous tissues, thus providing structural integrity and support to an organism
-CT also provides chemical support to other tissues; blood vessels and nerves run though CT to reach their destinations
-the ECM is the most abundant component of most CT and the properties of different types of CT are primarily determined by the composition of the ECM
-CT cells are often not connected to each other by cell-cell junctions
what are the two components of CT
cells and the ECM
what are the two types of cells in CT
-the fibroblast family makes and maintains this tissue. various cells will have different appearancs and names depending on location and activity
-bone marrow derived (immune system) cells are concerned with immune surveillance and defense. they travel through and reside in CT but dont contribute to its formation
what makes up the ECM (4)
- collagen fibers = most abundant protein type in mammalian body, primarily collagen type 1 or 2. eosinophilic in H+E and provide tensile strength
-reticular fibers = are actually collagen type 3 thin fibers that stain poorly with H+E. they form supporting network in some organs
-elastin fibers = usually stain very pale with H+E unless in large sheets, but have light refractive properties. they provide stretch-recoil function to CT
-ground substance = composed of water, PG, GAG, soluble proteins and other water soluble molecules. can appear as empty spaces because they dont stain well with H+E, and the spaces are often enlarged by shrinkage during processing
what is the main cell type we see in dense CT
fibroblasts
why does loose CT tend to have more cells compared to dense
because there are numerous immune system cells moving throughout
what is a special type of loose fibrous CT
reticular tissue
why dont reticular fibers (collagen type 3) react well with eosin
they are very thin and highly glycosylated
how are adipose cells connected
-NOT by cell to cell junctions but rather they are held in densly packed arrays of reticular fibers/collagen type 3 fibers
what type of adipose tissue has chicken wire type appearance
unilocular/white adipose tissue
what is the territorial matrix
more dense staining around the lacunae - it contains more GAGs
what are some types of cartilage? what is the most common
-hyaline cartilage is most common
-fibrocartilage
-elastic cartilage
what is on both sides of the cartilage? how does it stain and why
perichondrium - stains more eosinophilic compared to the cartilage because there is more collagen present
what is another name for perforating canal
volkmans canal
when are you able to see the interstitial lamellae
in cross sections of ground bone only