MadSci Network: Development |
You bet DNA specifies the size, shape, and location of all parts of our body. Like you've said, DNA for the most part encodes proteins which can have many different functions. Only a small part of the proteins in our body are actually structural..the kinds that are actually used to build tissues and organs and whatnot. Among the other types of proteins are proteins that are morphogens, which are normally used to define the location that special tissues and organs will form at during development. The size and shape of tissues are also dictated by proteins. These can include proteins that allow cells to move, or form different connections with other cells, or all of the other things that go into making the shape/size/ function of an organ. All of these things are encoded in the DNA. Hopefully this is good enough for a short answer. If you'd like an example of a much more detailed organization event, the link provided tells some information about what initially sets up the axes in an embryo. (What happens to change an egg into something that actually has a front vs. back, left vs. right, and head vs. tail.) It's pretty dense stuff, but would be a good place to start. Hope this helps. http://www.nimr.mrc.ac.uk/MillHillEssays/1996/morphgen.htm
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