NATS 1690 Lecture Notes - Chromosome, Y Chromosome, Color Blindness

• School: York University
• Department: Natural Science
• Course: NATS 1690
• Professor: Barbara Czaban

Document Summary

Linked genes tend to be inherited together because the chromosome is passed along as unit located on the same chromosome. Each chromosome has hundreds or thousands of genes, arranged linearly. Results of crosses with linked genes deviate from those expected according to independent assortment. A full linkage genes that are close together on the chromosome. Results in equal ratios of 2 types of gametes. The 2 genes with their respective alleles act as a unit during segregation. Incomplete linkage genes that are far apart on the chromosome. Results in unequal ratios of 4 types of gametes. The 2 genes are usually segregated as a unit. But crossing over may re-combine the alleles, thus shifting the ratios. Ratios of recombinant gametes will vary depending on chance. Proportional to the distance that separates genes. Crossing over will disrupt linkage between a and b more often than between.