Which of the following is true with regards to wound healing?
High-Yield Explanation
1.) At first a provisional matrix containing fibrin, plasma fibronectin, and type III collagen is formed, but in about 2 weeks this is replaced by a matrix composed primarily of type I collagen. 2.) After 4 weeks of wound healing, the strength of the wound is only 10%. 70% of the wound strength is only achieved after about 10-12 weeks of wound healing. 3.) The initial steps of wound contraction involve the formation, at the edge of the wound, of a network of myofibroblasts, which are modified fibroblasts exhibiting many of the ultrastructural and functional features of contractile smooth muscle cells. Within 6 weeks, large skin defects may be reduced to 5% to 10% of their original size, largely by contraction. 4.) Wound strength reaches approximately 70% to 80% of normal by 3 months but usually does not substantially improve beyond that point.