Recall that the nucleus of a cell contains chromosomes on which genes are located.
1. The nucleus of a cell contains chromosomes, which carry genetic information in a long molecule called DNA. (the double helix) Different Organisms have different amounts of Chromosomes. (Humans have 46)
2. Genes are regions of DNA that carry the code to control a particular cell activity or the production of a particular protein.
3. Chromosomes work in pairs. Known as homologous pairs. Homologous pairs are paired up by size/shape. One of the pair you inherit from your father, the other from your mother.
Homologous chromosomes pair during meiosis - the cell division that occurs as part of the creation of gametes (sex cells).
4. The same position/loci on the pair has the same gene (separate versions for one characteristic)
question: I don't understand the role of the locus.