| A | B |
|---|
| DNA | deoxyribonucleic acid - the molecule that contains genetic information |
| genes | short segments of DNA that contain the directions for particular proteins |
| chromosomes | threadlike structures made of DNA that contain many genes; become visible when tightly coiled for cell division |
| nucleotide | the building block of DNA and RNA; named for the nitorgenous base present (adenine, thymine, cytosine, guanine, uracil) |
| complementary base pairs | the two nucleotides that match up to form the DNA double helix, A with T (adenine and thymine) and C with G (cytosine and guanine) |
| DNA helicase | the enzyme that unwinds the DNA double helix during replication |
| DNA replication | copying the DNA molecule before cell division occurs |
| DNA polymerase | the enzyme that joins nucleotides to produce a new DNA strand during replication |
| mitosis | asexual cell division; one diploid parent cell produces two identical diploid daughter cells |
| diploid | cell containing two sets (pairs) of related chromosomes |
| haploid | cell containing a single set of unpaired chromosomes |
| meiosis | cell division for sexual reproduction; one diploid parent cell produces four haploid daughter cells |
| chromatin | uncoiled DNA present in the nucleus when the cell is not undergoing cell division |
