1. A virus consists of genetic material within a protective protein coat that allows it to enter a host cell. Viruses can infect cells through either a lysogenic or lytic cycle. 2. Bacteria are unicellular or multicellular prokaryotes that come in spiral, round, or rod shapes. They can be inhibited through processes like pasteurization, dehydration, freezing, or canning. 3. DNA carries genetic information in the form of genes and is composed of nucleotides with nitrogen bases that pair up in the helical structure. Cells use transcription and translation to read this genetic code and produce proteins.