Connective Tissue Flashcards
What is connective tissue proper?
1) Loose connective tissue
2) Dense connective tissue
- Either arranged irregularly or regularly in a parallel manner
Where are all connective tissues derived from?
Embryonic mesoderm which develops to embryonic mesenchyme.
What are the stem cells for connective tissue?
Mesenchyme
What do mesenchymal cells secrete?
Hylauronic acid-rich ground substances: function as fibroblasts
What resembles primitive mesenchyme?
Mucoid (mucous) connective tissue
Where is mucoid tissue found?
1) Umbilical Cord
2) Fetal organs
3) Pulp cavities of teeth
What is the most abundant cell in connective tissue?
Fibroblasts
What cell secretes the majority of the ECM?
Fibroblasts
What do fibroblasts secrete?
1) Collagen
2) Elastin
What are macrophages derived from?
Monocytes
What is the name for macrophages that reside in tissue?
Histiocyte
What are the functions of histiocytes?
1) Clear debris
2) Present antigens
3) Secrete growth factors
What are histiocytes in the liver?
Kupffer cells
What are histiocytes in the CNS?
Microglia
What are histiocytes in the bone?
Osteoclasts
What are histiocytes in the lung?
Alveolar macrophages
What are histiocytes in the skin?
Langerhans cells
What cell is derived from basophils?
Mast cells
What are mast cells filled with?
Basophilic granules that are metachromic and contain highly sulfated GAG (purple/red)
What are plasma cells derived from?
B lymphocytes
Why do plasma cells have abundant RER?
They are part of the immune system and produce A LOT of antibodies, which are proteins.
How are plasma cells identified at the LM level?
Clock-face appearance
What are the fibrillar collages that are mostly produced by fibroblasts?
1) Type I
2) Type II
3) Type XI
What is the location/function of collagen type I fibers?
Location: Skin, bone, tendon
Function: Resistance to tension
What is the location/function of collagen type II and XI?
Location: Cartilage
Function: Resistance to Pressure
What is the function/location of type III collagen?
Location: Reticular fibers of skin and vessels
Function: Structural support in expansion; comprises reticular lamina
What is the function/location of type IV collagen?
Location: Basal lamina
Function: Supports epithelial
What is the fxn/loc. of type VII collagen?
Location: Basement membrane
Function: Anchors basal lamina to reticular lamina
What is the structure of procollagen?
Triple helix
What kind of bonds stabilize procollagen?
Disulfide bonds
