BIOL 1123 Lecture 30: 17.2 Development in Animals
Document Summary
Segmentation genes: genes required for an embryo to develop a segmented pattern. Homeotic: changes in cell or tissue identity in which one body part is replaced by another. Gap gene: several adjacent segments are missing in the larva. Pair-rule genes: cause alternating segments or parts of a segment to be deleted. Segment-polarity genes: cause portions of segments to be missing either an entering or posterior region. The answer lies in gene regulation that controls cell differentiation. Stem cells have the capacity to divide to create one or more specialized cell types. Totipotent: can produce all the cell types in the adult organism. Blastocyst: stage of embryonic development that occurs before uterine implantation. Pluripotent: can differentiate into almost every cell type of the body but cannot create an entire intact organism by itself. Multipotent: can differentiate into several cell types but fewer possibilities. Unipotent: able to produce only cells of one type.