| A | B |
|---|
| DNA | hereditary material that controls all the activities of the cell, contains the information to make new cells and provides instructions for making proteins |
| nucleotide | a subunit of DNA consisting of a sugar, a phosphate, and one of four nitrogenous bases |
| adenine | one of four bases that combine with sugar and phosphate to form a nucleotide subunit of DNA; pairs with thymine |
| thymine | one of four bases that combines with sugar and phosphate to form a nucleotide subunit of DNA; pairs with adenine |
| guanine | one of four bases that combine with sugar and phosphate to form a nucleotide subunit of DNA; pairs with cytosine |
| cytosine | one of four bases that combines with sugar and phosphate to form a subunit of DNA; pairs with guanine |
| ribosome | a small organelle in cells where proteins are made from amino acids |
| mutation | a change in the order of bases in an organism's DNA; can be a deletion, insertion, or substitution |
| mutagen | anything that can cause damage or cause changes in DNA |
| pedigree | a diagram of family history used for tracing a trait through several generations |
| double helix | twisted ladder shape of DNA |
| replicate | to make a copy |
| incomplete dominance | each allele has its own degree of influence; both traits show up |
| deletion | form of mutation where a base is left out |
| insertion | form of mutation where an extra base is added |
| substitution | form of mutation where an incorrect base replaces a correct one |
| selective breeding | organisms with desirable characteristics are mated to produce a new breed |
| genetic engineering | scientists transfer genes from one organism to another |
