Development of skeletal tissues

Question 1

Embryonic connective tissue

Answer 1

cells are mesenchymal as opposed to epithelial and in ECM either as scattered individal cells or aggregates

many cells to ECM

Fibrous proteins embedded within a very hydrated amorphous ground substance mainly of proteoglycans and hyaluronic acid

Question 2

mature connective tissue

Answer 2

cells in ECM ranges from sparse to abundant

usually predominates High ECM to CT cells

loose and dense fibrous CT, bone cartilage and bone and lymph

Question 3

skeletal tissues develop from mesenchyme

Answer 3

skeletal tissue forming mesenchyme (STFM)

in trunk STFM originates from the scleratome of somites

preskeletal condensation (specific transcription factors (Sox 9 and Runx2)

Question 4

primary differentiation path of STFM

Answer 4

Cartilage - if its to become cartilage– sox 9 causes them to become chondroblasts that secrete type 2 collagen

Chondrification center

Of bone Runx2 (intramembranous ossification), osteoblasts