Biological engineering deals with engineering biological processes in general. It is a broad-based engineering discipline that also may involve product design, sustainability and analysis of biological systems. Generally, bioengineering may deal with either the medical or the agricultural fields. The term can be applied more broadly to include food engineering and biotechnology. Biological engineers are similar to biologists in that they study living organisms. They are engineers because they have a practical design aim in mind - they use research to create usable tangible products. In general, biological engineers attempt to 1) mimic biological systems in order to create products or 2) modify and control biological systems so that they can replace, augment, or sustain chemical and mechanical processes The modifying of plants or animals by breeding, which has been practiced for thousands of years. The modern, recombinant DNA based biotechnology is a more powerful version of existing technology The recombinant DNA biotechnology allows us to take virtually any gene and express it in any organism; we can take the genes that make crimson color in plants and put them into guinea pigs to make pink pets, or, we can take the genes that help arctic fish survive the freezing temperatures and put them into food to increase the amount of time it can grow before it freezes. This sort of gene transfer was virtually impossible with historical processes. http://en.wikipedia.org/wiki/Bioengineering http://en.wikipedia.org/wiki/Biotechnology