lecture 9 Flashcards
what are the 5 major types of connective tissue?
- bone
- tendon
- cartilage
- derma (skin)
- fascia
what are some examples of specialised connective tissue?
- umbilical cord
- kidney cortex
what do connective tissues have in common?
- relatively few cells
- lots of extracellular material/matrix
what are the fibres found ?
- elastin and collagen
how are they arranged?
- in parallel or crisscrossed meshwork
what are connective tissue characteristics relative to?
- fibrillar proteins
- proportions of collagen and proteoglycans
what are proteoglycans?
- specialised form of glycoprotein
what are the 3 main types of cartilage?
- hyaline (in joints)
- fibrous (annulus fibrosus, repair)
- elastic (elastin, ear lobes, epiglottis)
what is hyaline cartilage?
- covers bone articulating surfaces (joints)
- forms distal ends of ribs
- forms cartilaginous plates of nasal septum, larynx, trachea and bronchi
- firm and flexible
what is the flexibility of hyaline cartilage due to?
- proteoglycan content
what is the rigidity and tensile strength of hyaline cartilage due to?
- collagen content
what is the structure of the synovial joint?
- 2 bones
- capsule containing synovial fluid (lubrication of joint)
- cartilage layer on surface
- perichondrium on top (skin thin)
how does the cartilage gain nutrients?
- synovial fluid as in contact with blood
- up through subchodral bone
what are the characteristics of cartilage?
- no nerve supply
- not innervated with blood or neves
- immune privileged as no blood supply (no surveillance from immune system)
- low chondrocyte nutrient supply
what is found in an immobilised joint?
- hydroxyproline increased in blood
what is the structure of hyaline cartilage?
- collagen criss cross matrix
- spaces filled with proteoglycans (neg charged)
- lots of water held
- net structure used to minimise swelling pressure
what gives proteoglycans its negative charge?
- carboxylic acid groups
- sulphate groups
what is the composition of collagen?
- 30% glycine
- 30% proline/hydroxyproline
- hydroxylysine
- made of many tropocollagen molecules aggregated together so insoluble
what is tropocollagen?
- type 2 trans helix
- has hydrogen bonds holding together
- regular composition of glycine-a.a-a.a-glycine etc.
what is the composition of scurvy?
- proline + vitamin C forms HO-proline
- without cant form hydroxylproline
what is osteoarthritis?
- stiffening and pain in joints
what is osteoarthritis caused by?
- protective cartilage on bones breaking down
what are current treatments of osteoarthritis?
- focused on symptomatic release
- no medical intervention yet to control progression of disease
what crosstalk causes osteoarthritis?
- cartilage and subchondral bone
- deterioration of one causes damage to other
