Connective Tissue Flashcards
Functions of Connective Tissue
- It binds, supports and strengthens other body tissues.
- A major transport system of the body (blood).
- A major site of stored energy reserves (fat or adipose tissue ).
Unlike epithelia • CT is NOT found on \_\_\_\_\_\_\_\_\_\_\_\_\_ (bones, cartilage, blood) • CT can be highly \_\_\_\_\_\_\_\_ – (Exceptions: cartilage and tendons with v little blood supply) Like Epithelia • CT is supplied by \_\_\_ – (Exception: cartilage)
body surfaces. vascular
Nerves
Connective tissue (CT) is composed of:
EXTRACELLULAR MATRIX (ECM) and CELLS CT = ECM + Cells
The ECM is composed of :
i) Ground Substance (GS) in association with
ii) 3 different Protein Fibres
ECM = GS + Fibres
Ground substance is composed of a mixture of :
• Water • Proteins (gelatine in jelly!) • Polysaccharides (sugars) GS = H2O + proteins+ polysaccharides The sugars include: Glycosaminoglycans (GAGS or mucopolysaccharides).
GAGS join with core proteins to form …
proteoglycans.
Non-sulphated GAG
• Hyaluronic acid is not covalently bound to a core protein. but
is joined to various PGs
Hyaluronic Acid GAG Applications :
viscous slippery substance binds cells
together lubricates joints and maintains shape of eyeball
Hyaluronidase GAG Applications :
produced by white blood cells, sperm
and some bacteria.
Application of GAGS as part of
ground substance
Chondroitin Sulphate: support and provide the adhesive
features of cartilage, bone, skin, blood vessels.
Keratan Sulphate: found in bone, cartilage, cornea of the eye
Dermatan Sulphate: found in skin, tendons, blood vessels,
heart valves
Sulphated GAG examples:
- Dermatan sulphate
- Heparin sulphate
- Keratan sulphate
- Chondroitin sulphate
Periorbital ECM and
thyroid disease
thick periorbital
tissues. eye popping
There are 3 different types of connective tissue fibres
in the extracellular matrix (ECM):
i) Collagen fibres (thick)
ii) Reticular fibres
iii) Elastic fibres
i) Collagen fibres
Very strong but flexible to resist pulling forces
around collagen in cartilage than in bone.
• Collagen 25% of your body, most abundant
protein
Reticular fibres
Composed of collagen
• Collagen in fine bundles with coating of
glycoprotein (more protein than sugar)
• Made by fibroblasts
• Provide strength and support
• Form part of the basement membrane
• Thinner, branching - spreads through tissue.
• Form networks in vessels and through tissues
Elastic fibres
Thinner than collagen fibres
• Fibrous network
• Consist of the protein elastin surrounded by the
glycoprotein fibrillin to give more strength and
stability.
• Can be stretched 150% without breaking
• Found in skin, blood vessels and lung
Marfan Syndrome
hereditary defect in elastic fibres-fibrillin.
Body produces growth factor Transforming
Growth Factor beta(TGFb) – increases growth
because does not bind normally to fibrillin to
keep it inactive
Connective Tissue Cell Fibroblasts Location and Function
Widely distributed in connective tissues; migratory Secrete components of the matrix (fibres and ground substance)
Connective Tissue Cell Adipocytes
(fat cells) Location and Function
Under skin and around
organs
Store fat
(triglycerides)
Other cells found in Solid CT
Macrophages (Phagocytic cells), Plasma cells ( from lymphocyte, produce antibodies) Mast cells (Produce histamine that dilates vessels) Leucocytes (White blood cells)
