Term
| Distinguish the 5 major types of collagen by polypeptide chains and tissue distribution. |
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Definition
Type I: 2 distinct chains. Skin, Tendon, Bone Type II: 3 identical. Cartilage, Vitrous humor (eye) Type III: 3 identical. Skin, Blood vessels, lung, fresh scars. Type IV: 2 distinct. Basement membranes Type V: Most connective tissue. Associated with Type I |
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Term
Describe the biochemical mechanisms for Homocysteinuria and Menks Disease, compare them to Lathyrism. |
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Definition
Menkes- decrease crosslinking due to copper malabsorption. Homocysteinuria- genetic defect do to inhibition of cystathionine synthase. (which condenses it's substrate homocystein) resulting in abnormal collagen crosslinking due to the (SH) binding with collagen. Lathyrism- Abnormal cross-linking due to inhibition of lysyl oxidase. Penicillanine chelates the Cu ions needed and also inactives it. |
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Term
| List diseases or disorders of collagen due to a genetic defect and those due to a deficiency or inhibitor. |
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Definition
Genetic: Ethers-Danlos(many), Homocysteinuria(cystathionine synthetase), Osteogenesis Imperfecta(Type I). Deficiency: Scurvy(Vitamin C) Inhibition: Lathyrism(lysyl oxidase inhibitor) |
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Term
| Describe the structure and function of adhesive glycoproteins. |
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Definition
Proteins are Fibronectin and Laminin. Function: Wound healing, Cell attachment, Cell migration, Cell spreading, Chemotaxis(directing movement according to certain chemicals) |
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Term
| What are the different GAGs and their functions? |
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Definition
Dermaten Sulfate: inhibit blood clotting (anticoagulant) Chondroitin Sulfate: structural component of cartilage. Resistant to compression. Keratan Sulfate: can act as a cushion to absorb mechanical shock in joints. Hyaluronic Acid: Acts as the core to which proteoglycans attach to form proteoglycan aggregate. |
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Term
| Describe disorders of proteoglycan degration(mucopolysacchoridosis). Diseases of GAG metabolism. |
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Definition
Hurler Syndrome: a-L-iduronidase (dermaten-s, heparan-s) Hunter Syndrome: L-iduronate-2-sulfatase (dermaten-s, heparan-s) Sanfilippo Syndrome: many (heparan-s) |
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