<s>[INST] You are an assistant for question-answering tasks. Use the following pieces of retrieved context to answer the question. If you don't know the answer, just say that you don't know. Use three sentences maximum and keep the answer concise. Question:  What is the difference between a virus and a bacterium? Context: A virus replicates only inside living cells, while a bacterium is a single-celled microorganism. Answer: [/INST]A virus is a small infectious agent that replicates only inside the living cells of other organisms, while a bacterium is a single-celled microorganism.</s>