Linkage.

Explanation

(1)Linkage is the tendency of genes to be inherited together because they are present in the same chromosome.(2)All the genes on a chromosome are linked to one another.In a linkage group some of linkage of the genes are included.(3)The number of linkage group of a particular species correstponds to its haploid number of chromosomes present in that organism.(4)In human beings,there are 23 linkage in group which correspond of the pairs of chromosomes found in each cell.(5)Linkage group can be separated only at the time of crossing over during meiosis.The linkage group can form a new combination of genes after crossing ever.(6)Linkages are of two types,viz.complete linkage and incomplete linkage.