LIFESCI 2A03 Lecture Notes - Lecture 3: Somatic Cell, Mitosis, Axolotl
Document Summary
Regeneration the regrowth of lost or destroyed parts or organs. Individual stem cells are losing identity as stem cells assuming identity of root cells plant. Separate cells from carrot, culture cells, individual cells will then be able to generate entire new plant. Regeneration in plants illustrated: plants always growing, figure: arabidopsis root regeneration. Planaria non-parasitic flatworm that exhibits an extraordinary ability to regenerate. Figure: cut in 3 places; all 3 pieces can regenerate to full planaria. Steps: muscular contraction to limit size of cut surface, thin wound epithelium forms over surface, accumulation of undifferentiated cells (neoblasts) in the blastema, growth and differentiation of blastema. Polarity: the first decision that the blastema makes is what portion of the body to regenerate: head or tail difference in polarity. Information is contained within amputated fragment: mechanism for polarity is not known. Studies to try to identify the mechanism have come from: