BIOL 102 Lecture Notes - Lecture 22: Cell Potency, Blastula, Embryogenesis
Document Summary
An embryo contains all of its descendants in sperm or egg. Fertilized egg zygote 2 blastomeres 4 blastomeres. Cells of an embryo that retain the potential to form a full individual. Potency is progressively restricted during development leading to determination. Animals are only totipotent in early embryos. Marked cells and followed what they become (map embryos) If you move some parts and implant them somewhere else. Movement of cells change their original function. Position of cells tells the cells what they will become! Cells in blastula still retain ability to form a full individual. 80% fully formed frogs when embryo is 20 hours old. Easier to reconstruct a plant from cell structures: define: developmental processes. Determination: sets the developmental fate of a cell (what type of cell it will become) ex: mesenchyme cells become connective tissue. Point at which a cell becomes committed to a particular fate. Cell"s environment and contents influence this process.
