In autosomal chromosome pairs, the two homologous chromosomes are always the same size and shape. But in the case of sex chromosomes, in females, the two sex chromosomes are the same size and shape. But in males, we have one large sex chromosome and one small sex chromosome. So that means we have two homologous chromosomes that are not the same shape and not the same size. So to see what we mean by that, let's take a look at the following three diagrams. So we have diagram A, diagram B and diagram C. Now, in diagram A, we have an autosomal chromosome pair.