Akaryotes

Question 1

Are viruses living things?

Answer 1

No they are not living things. Viruses are acellular - they are not cells, they do not contain any organelles

Question 2

What is the general viral structure?

Answer 2

Consist of:
- nucleic acid (genetic material i.e DNA or RNA)
- capsid (protein coat)
- attachment proteins

Question 3

Describe viral replication

Answer 3

1. Viruses attach to hosts cell surface. Their attachment proteins bind to complementary receptor proteins on host cell
2. Genetic material (DNA or RNA) is released into the host cell
3. Genetic material and proteins are replicated by ribosomes
4. Viral components assemble
5. Replicated viruses are released from the host cell

Question 4

Why can some viruses only infect one type of cell while others can infect lots of different cells?

Answer 4

Different viruses have different attachment proteins and therefore bind to different receptor proteins on host cells