Biotechnology uses genes from different organisms to modify biological functions and create products to benefit society. It has applications in gene therapy, cancer treatment, vaccines, and more. Techniques include adding genes to crops to increase vitamin levels or tolerance to environmental stresses. DNA is delivered using organisms like Agrobacterium. Medical biotechnology aims to prolong life through monoclonal antibodies, bioprocessing insulin from bacteria, stem cell therapies, and tissue engineering to replace damaged tissues.