1. You have identified a novel organism that has only four cell types (neural, muscle, gut, and germ cells) and twenty-one cells in the adult. You sequence its entire genome and to your overwhelming surprise discover that after you have accounted for all of the housekeeping genes (genes necessary to keep cells alive which are expressed in each and every cell) and all of the terminal differentiation genes (genes required for the final phenotype of an adult cell, for example, the sodium channel in neural cells), there are only twenty five (25) genes left. Propose how these twenty genes can give rise to this novel organism from the one cell stage through cell type differentiation in the adult. You should sketch your organism at each cell division (you will need at least five "waves" of synchronous division to get to 21 cells) showing which genes are expressed in each of the cells (and which genes they regulate to produce the phenotype); drawing the promoter/enhancer region of selected genes would be an effective way of showing gene regulation. Please be sure to explain your proposed logic for the development of your organism. (You may arrange the cells in your organism in any way you choose). You can use real genes or genes that you "make up" - but be sure to explain their function (e.g. transcription factor) and ground them in reality.
2. Select an article pertaining to developmental biology from the popular press (newspaper article, magazine article, website). Then find the actual scientific article upon which this article was based. In light of the actual scientific article, present a critical analysis of the popular press article. Was it well written? Was it accurate? Did it omit critical data? Please select a unique article; so please post your topic under the "article" discussion thread on BB.
3. From Circe and Arachne, to the Nagas of Hindu mythology to the Shapeshifters of X-Files, Dr. Who, and Star Trek - Shapeshifting has captured human imagination from the dawn of history. First, pick a Shapeshifter (from literature or from popular culture) and describe the embryonic development of the creature that allows it to shapeshift later in life, and then describe the molecular-cellular-tissue mechanisms by which it actually undergoes the shift later in life. Be sure to describe the inducing factor - be it genetic, environmental or psychological that initiates the shift. You may use real genes or postulate genes that evolved in this creature; either way, explain the function of the gene/protein. You have license to be creative - but really good science fiction is always based at least somewhat on good science! You should pick a Shapeshifter that no one else has selected, so please put your choice on the BB Discussion site in the Shapeshifter thread. Simply enter it in the Subject Box.
4. For class you have read two "Hallmarks" papers (on Aging and Cancer) - papers published in the premier journal "Cell," that attempt to articulate the salient features of a given process or disease. Using these papers as a guide, choose ONE aspect of developmental biology (other than aging or cancer) and identify what you regard as the "Hallmarks" of that aspect of developmental biology. Your topic can be as narrow or broad as you wish. These should be the "big ideas" that you (hopefully!) remember as the guiding mechanisms of development years from now! Select a feature that no one else has selected; please post your topic under the "Hallmarks" discussion thread on the BB site.
Attachment:- Assignment File.rar