Are homologous pairs of chromosomes exact copies of each other?

No, they are not because the alleles at a gene on the pair of homologous chromosomes contributed by both parents may be different. One pair of homologous chromosomes comes from the father while the other pair comes from the mother. A pair of homologous chromosomes contains one maternal and one paternal chromosome that pair up with each other during meiosis. When a parent cell divides into two or more daughter cells; each daughter cells obtain one half of the duplicated set of chromosomes which may or may not. During meiosis the alleles at a gene may or may not be the same producing different phenotypes.