Purines have 2 rings pyrimidines have 1 ring.
Penelope is most likely to be dependent on caffeine.
1. The science of classifying living things is called taxonomy. Linnaeus introduced the classification system that forms the basis of modern classification. Taxa in the Linnaean system include the kingdom, phylum, class, order, family, genus, and species. ... The domain is a broader taxon than the kingdom.
2. Don't travel by air if you can avoid it because air travel uses up large amounts of fossil fuels and creates greenhouse gases. Dispose of any rubbish responsibly - it can be hazardous to wildlife. Use public transport, cycle or walk instead of using a car. Use facilities and trips run by local people whenever possible.
Hope this helps!
Viruses <u>use the host cell to copy themselves and make viral proteins</u>.
Prophase, Metaphase, Anaphase, and Telophase
