How do cells choose which type of cell to become during embryonic development? The first few embryonic cells give rise to all other cells. They are called totipotent, or pleuripotent. Cell fate decisions result in differentiation into all cell types in an organism.
Developmental processes Cell-autonomous developmental restrictions –Common in C. elegans Positional information / intercellular signaling Morphogen- a molecule the participates directly in control of growth and development.
Use of cell transplantation during early embryonic development to ascertain the timing of fate determination
The first 3 divisions during the development of the worm Caenorhabditis elegans
Transplantation of extra cells during early development of sea urchin results in abnormal development
A female worm Caenorhabditis elegans There are two kinds of worms- hermaphrodites (XX) and males(XO). 60 hours from egg to adult (at 20 C), 300 eggs produced in a few days, 10,000 on a petri plate. Transparent bodies have 959 somatic nuclei.
A cell lineage diagram showing a cell that undergoes programmed cell death (apoptosis) and three that become differentiated