Hi, I had a couple of random bio 3/4 questions that I haven't been able to find definitive answers to:
1. Regarding the BMP4 protein/gene (obviously this is new to the study design but I thought I may as well ask if you knew much about it), I read in a textbook that it was a master control regulatory gene, which codes for the protein BMP4, which is a signalling protein that regulates the expression of multiple structural genes that define distinctive characteristics such as beaks, jaws etc. Thus, mutations to the BMP4 gene result in the novel variations of these traits due to altered expression of the BMP4 protein... is this correct? I recently came across a source that said the BMP4 protein was the same in different organisms, hence the mutations did not occur to the BMP4 gene but a different regulatory gene that regulates BMP4 gene expression? I am aware that may not make any sense... but this confused me as it sounded like a regulatory gene regulating a master regulatory gene... If anyone could clarify BMP4 gene, the function of its protein product BMP4, and where these mutations occur, that would be awesome
2. In the allergic response, the production of (igE) antibodies is stimulated by the entry of an allergen to the body. Does this mean our body contains B cells/antibodies that are specific to and activated by normally harmless antigens? Or only in some people? The initiation of the allergic response when the allergen is identified is confusing me a bit.
3. Is there a definitive/worth noting difference between selective agent and selection pressure? I've read that they are separate (i.e. a selective agent inflicts a selection pressure on an environment), but when looking for examples of either they usually give the same factors, such as disease or predation. Is there a difference and would anyone be able to demonstrate this with clear examples?
4. Finally, this isn't so much to do with the course but I've gotten different responses to this question. It was on the VCAA sample exam, regarding whether raw data or averaged data should be used when drawing conclusion from experiment results. I believe you said to go with raw data, and I was just wondering why? It would've been my initial response too but I had a teacher tell me and a practice exam lean towards use of averaged values.
Thanks heaps!!