When dna is copied sometimes a new incorrect base pairing appears within the structure of a new dna molecule replacing original base pairs this mistake is called a base pair

Ascientist is conducting an investigation that involves water, silver, carbon dioxide, and oxygen gas which group of statements best describes all of the materials he is using in the investigation?

Which macromolecule catalyzes chemical reactions this be considered enzyme chemical reactions thus he considering enzymes

Fossils of ancestors of the modern horses show a small 4-toed almost dog-like browsing animal named eohippus over time the horses got larger lost toes and changed to a grazing diet what is the best explanation of why this change occurred