S6 Connective Tissue Flashcards
What 3 components is connective tissue made of?
- Cells (fibroblasts, adipocytes and reticular cells)
- Fibres (collagen, elastin and reticular fibres)
- Ground Substance (proteoglycans - GAGs e.g. hyaluronic acid)
What makes up the extra cellular matrix?
Ground substance and fibres
What are the 6 functions of connective tissue?
- Binding and supporting
- Protecting
- Insulating
- Storing reserve fuel and cells
- Transporting substances within the body
- Separation of tissues
Examples of connective tissue binding and supporting?
Holding skin, gut, lung, etc. together
Examples of connective tissue protecting?
Bone protects vital organs and fat acts as a shock absorber
Example of connective tissue insulating?
Fat underlying skin
Examples of connective tissue storing reserve fuel and cells?
Bone marrow and fat tissue
Examples of connective tissue transporting substances around the body?
Blood and interstitium (space between tissues and organs of the body)
Examples of connective tissue separating tissues?
Fascia and tendons and cartilage
What is connective tissue proper?
General connective tissue - loose and dense (irregular/regular) connective tissue
What is loose connective tissue also known as?
Areolar tissue
What is another name for dense connective tissue?
‘Fibrous’ or collagenous tissue
What are 3 examples of loose connective tissue?
- LAMINA PROPRIA is part of the mucosa (under to basal lamina of epithelial cells, above muscularis mucosae)
- Surrounding capillaries, nerves and sinusoids
- Around glands
What are the two types of dense connective tissue?
- Irregular (fibres run in different directions)
2. Regular (fibres run parallel to each other)
What are the two main types of fibre in loose connective tissue?
Collagen and elastic
What are the main cell types in loose connective tissue?
- Fibroblasts
- Macrophages
- Other WBC
- Mast cells
- Adipocytes
What are fibroblasts?
Why are they important?
Cells that synthesise and secrete fibres that are in the ground substance.
Important in wound healing process - involved in formation of scar tissue.
What are myofibroblasts?
Fibroblasts that contain actin and myosin - responsible for wound contraction when tissue loss has occurred
What do mast cells contain?
Where are they found?
Contain granules:
histamine (increase blood vessel wall permeability) heparin (anticoagulant)
cytokines (attract eosinophils and neutrophils)
Found in loose connective tissue, near blood vessels (not found in CNS)
(look like basophils)
What do mast cells do?
Bind to IgE molecules (bind to allergens).
When an allergen binds to IgE on mast cell surface, granules are released.
What are adipocytes?
Fat storage cells
What is white adipose tissue?
Have only one lipid droplet per cell and a normal number of mitochondria.
Organelles squashed to side of cell.
Used for padding/shock absorber, insulation and as an energy reserve.
Found in adults.
Slow lipid breakdown.