| A | B |
|---|
| Histones | help maintain the shape of the chromosome and aid in the tight packing of DNA. |
| Nonhistones | involved in controlling the activity of specific regions of the DNA |
| Chromatid | half of a chromosome form as the DNA makes a copy of itself before cell division. |
| Centromere | The constricted area of each chromatid. Holds the two chromatids together until they separate during cell division |
| Sex chromosomes | determine the sex of an organism may also carry genes for other characteristics. 2 of the 46 human chromosomes are sex chromosomes |
| Autosomes | all other chromosomes in an organism |
| Homologous chromosomes | two copies of each autosome they are the same size and shape and carry genes for the same traits |
| Karyotype | a photomicrograph of the chromosomes in a dividing cell found in a normal human. |
| Diploid cells | have 2 sets of chromosomes |
| Haploid cells | have only 1 set of chromosomes Human sperm and eggs cells. |
