Compare and contrast a bacterium and a virus by writing either “Present” or “Absent” for each of the following structures.

Verified step by step guidance

1. Step 1: Understand the basic differences between bacteria and viruses. Bacteria are prokaryotic cells with cellular structures, while viruses are acellular entities that require a host to replicate.
2. Step 2: For the 'Cell membrane' structure, recognize that bacteria have a cell membrane as part of their cellular structure, so mark 'Present' for bacterium. Viruses do not have a cell membrane, so mark 'Absent' for virus.
3. Step 3: For 'Functional ribosome', bacteria have ribosomes to synthesize proteins, so mark 'Present' for bacterium. Viruses lack ribosomes and rely on the host's ribosomes, so mark 'Absent' for virus.
4. Step 4: For 'Cytoplasm', bacteria contain cytoplasm as the site of metabolic activity, so mark 'Present' for bacterium. Viruses do not have cytoplasm, so mark 'Absent' for virus.
5. Step 5: For 'Nucleic acid', both bacteria and viruses contain nucleic acid (DNA or RNA) as their genetic material, so mark 'Present' for both bacterium and virus. For 'Nuclear membrane', bacteria lack a nuclear membrane because they are prokaryotes, so mark 'Absent' for bacterium. Viruses also lack a nuclear membrane, so mark 'Absent' for virus.

Key Concepts

Cell Membrane

The cell membrane is a lipid bilayer that surrounds the cytoplasm of cells, controlling the movement of substances in and out. Bacteria, as living cells, have a cell membrane, while viruses lack this structure because they are not cellular and rely on host cells for replication.

Functional Ribosome

Ribosomes are cellular structures responsible for protein synthesis. Bacteria contain functional ribosomes to produce their own proteins, whereas viruses do not have ribosomes and depend entirely on the host cell's ribosomes to translate their genetic material into proteins.

Nucleic Acid and Nuclear Membrane

Nucleic acids (DNA or RNA) carry genetic information in both bacteria and viruses. Bacteria have nucleic acid enclosed within a cytoplasm but lack a nuclear membrane, as they are prokaryotes. Viruses contain nucleic acid but do not have a nuclear membrane or cytoplasm, as they are acellular entities.