International A Level Biology / Mitosis, meiosis and reproduction

Loci and linked genes

Edexcel International A Level Biology (YBI11), chapter 8: Mitosis, meiosis and reproduction, specification point 3.9. Part of the full course.

Read the revision notes · International A Level Biology past papers

A locus is the position of a gene on a chromosome. Genes with loci on the same chromosome are linked, so they tend to be inherited together unless crossing over separates them.

More lessons in Mitosis, meiosis and reproduction

• The cell cycle
• The stages of mitosis
• Core practical 6: the root tip squash
• Calculating the mitotic index
• Meiosis: two divisions, four haploid cells
• Independent assortment and crossing over
• Sperm and egg: specialised gametes
• Fertilisation in mammals
• Fertilisation in flowering plants
• Investigating pollen tube growth