1 Flashcards
Three features of cells and extra cellular matrix
-flexibility strength and protection- collagen
-elasticity-elastin
Binding of water- proteoglycans
What are the 5 cell types in connective tissue
Fibroblast
Adipose fat
Mast cells
Macrophage
Plasma cells
What are fibroblasts
Main cells of CT synthesise and maintain ECM
ECM contains three main components: fibrous component- elastin and fibres
Amorphous component- proteoglycans
Main component is the fibroblasts
Explain the connective tissue type adipose
Fat, energy store, thermal insulator/shock absorber to protect cells and tissues.
Explain the connective tissue cell mast cells
Secrete histamine and help initiate inflammatory response
Explain the connective cell tissue type macrophage
Main phagocytise cell can present antigens
Explain the connective tissue cell type plasma cells
Derived from b lymphocytes synthesise antibodies
Types of collagen fibrous
Type1- pink wavy fibres with H and E stain
Type 2 cartilage made by Chondrocytes (which also produce elastin fibres and ground substance in cartilage
Type 3 reticular fibres delicate supporting framework in organs e.g liver- black with silver stain
Type 4 basal lamina basement membrane acts as support for tissues and micro filter in kidney
Type 5 embryonic tissue
Describe collagen synthesis
Type 1 pro collagen peptide in fibroblast
Secreted pro collagen peptide
Cleavage of pro collagen
Self assembly into fibrils
When overlap dense region
When non overlap light reguon
Collagen has dense and light areas
Overlap and non overlap
What is scurvy
Vitamin c deficiency- defective collagen synthesis
Degeneration of connective tissue
Thinning of skin sunken eyes loss of teeth
What are the symptoms of scurvy
Thinning of skin/sunken eyes loss of teeth
Describe type 4 collagen- basal lamina
Extra cellular matrix receptors on the surface of cells which allow them to be anchored into the extra cellular matrix.
ECM receptors attach cells to the ECM by binding to a special ECM structure- the basal lamina (basement membrane)
Collagen four and laminin form layer on outside of cell membrane by binding to ECM receptors.
Describe type 4 collagen- basal lamina
Extra cellular matrix receptors on the surface of cells which allow them to be anchored into the extra cellular matrix.
ECM receptors attach cells to the ECM by binding to a special ECM structure- the basal lamina (basement membrane)
Collagen four and laminin form layer on outside of cell membrane by binding to ECM receptors.
Do smooth muscle cells have several nuclei per cell
Yes
Features of elastin fibrous
Made of elastin protein
Synthesised by fibroblasts in precursor form as tropoelastin
Tropoelastin released into the ECM and binds with another molecule before forming elastin.
Deposition in form of fibres requires microfibrils of fibrillin (a structural glycoprotein)
Microfibrils are damaged by sunlight
Vitamin A repairs microfibrils that are damaged by sunlight.
Proteoglycans (amorphous)
What is the normal stain for histological stains
Haematoxylin and eostine H and E
H stains nuclei blue/purple
E stains protein pink and red
List the four structures of proteoglycan
Linker protein
Core protein
Hyalurin molecule
GAG glycos amino glycan
How do proteoglycans resist compression
H20 binds to the GAG glycos amino glycan and GAG is hydrophilic so gels formed which resist compression.
Why does skin degrade
Collagen elastin and GAG glycos amino glycan decrease with age
Features of fat cell type in connective tissue
Mechanical buffering energy store
Fat- adipose tissue consists of adipocytes nucleus pushed to one side contains one large lipid droplet
Features of cartilage
Semi rigid support
Cartilage is hard due to tightly bound water molecules
3 types elastic hyaline and fibrocartilage
Cells of cartilage chondracytes. Perichondrium have Chondrablasts and stem cells that make chondracytes.
Type three collagen reticular fibres are:
Delicate supporting framework
In many cellular organs
Lymph nodes endocrine glands and liver
Stain black with silver stain.not h and e stain
Elastin fibres what stains are used for them
Special stains black
Cross links between single elastin molecules.
In arteries tunica intima
Loose connective tissue
Mesh work of elastin fibres inside mesh work is proteoglycans GAGS and linker proteins.
And collagen fibres
what is the extracellular matrix
the relationship between collagen, elastin, and proteoglycans and water.
