PeerWise

Question 1

Functions of the proteins in ECM

Answer 1

Collagen= determines tensile properties of connective tissue
Elastin= Determines elasticity of connective tissue
Fibrillin= Forms microfibrils that act as a scaffold
Fibronectin= Acts as an attachment point for anchoring cells and fibres

Question 2

Describe fibroblasts

Answer 2

• Flat, spindle shaped, irregular border
• Large nucleus, many mitochondria and secretory vessels
• Active synthesis and secretion of ECM and some degradative enzymes
• Mainly type one collagen and small prostaglandins

Question 3

Describe osteogenesis imperfecta

Answer 3

child with fractures, deafness and blue sclera = osteogenesis imperfecta. Osteogenesis imperfecta occurs due to an abnormality in type 1 collagen. Type 1 collagen is present in the skin, tendons, vasculature and bones. The abnormality leads to brittle bones which caused the multiple fractures in this case

Question 4

Where are the different types of collagen?

Answer 4

• Type 1 collagen is present in the skin, tendons, vasculature and bones.
• Type 2 collagen is present in cartilage
• Type 3 collagen is the main component of reticular fibres
• Type 4 collagen makes up our basement membranes
• Type 5 collagen is present in cell surfaces and hair cells

Question 5

What kind of cartilage is used in enthesis?

Answer 5

Fibrocartilage