biology is the branch of science that deals with living organisms and life processes.
technology is the use of tools and processes, materials, the way people use them, to make our lives better - we hope
bio-technology is the way that people change living organisms and life processes using tools (ex. cochlear implant), processes (ex. cloning) or materials (ex. drugs) to make our lives better - we hope.
engineering is the process of envisioning, designing and building solutions for human technological wants and/or needs.
ethics is a branch of philosophy dealing with what is good or bad - the rules of moral conduct governing individuals or a group.