Final answer:
Plant cells are useful as hosts for recombinant DNA because they can be genetically engineered to produce transgenic plants. They can overcome the challenge of their thick cell walls by removing them and using a gene gun to shoot recombinant DNA into the plant cells. Agrobacterium tumefaciens can also be used to naturally transfer DNA fragments into plant hosts.
Step-by-step explanation:
Plant cells are useful as hosts for recombinant DNA because they can be genetically engineered to produce transgenic plants. The thick cell walls of plant cells can be overcome by using enzymes to remove the cell walls and shooting recombinant DNA-coated particles into the plant protoplasts using a gene gun. This enables the plant cells to recover and generate new transgenic plants. Another method involves using Agrobacterium tumefaciens to naturally transfer DNA fragments into plant hosts. The Ti plasmids of Agrobacterium tumefaciens can be engineered to integrate desired DNA fragments into the plant cell's genome, resulting in the production of transgenic plants.