Exer 3

• Linkage group are all the genes carried in a given chromosome
• The no. of linkage groups in an organism is equal to its HAPLOID chromosome number
• Linkage is the physical association of non-allelic genes in the same chromosome
• Two genes located in two different homologous chromosomes are independently segregating
• Two genotypes of progeny is called parental types
• Counterpart of parental types is called recombinant types
• Frequency of recombinant types is 50%
• Complete linkage is when two or more non-allelic genes are closely located in linear order on same chromosome
• Complete linkage do not assort independently from each other
• Two or more non-allelic gene on the same chromosome are far apart is called incompletely linked
• Less than 50% recomb frequency means an incomplete linkage
• A gene producing a phenotype often unrelated to sex located on a sex chromosome is called sex linkage
• Men are called hemizygous for the X-linked genes