Almost all cells in an animal (except gametes) have __ sets of chromosomes? in other words, how many homologs for a particular chromosome?

The answer is 2. This is why their autosomal cells are referred to as diploid in chromosome number. The gametes have only one set of chromosomes. The homologous pair (sister chromosome) separate during meiosis I. If there was an extra chromosome in addition to this set then this would cause a condition called aneuploidy.

Almost all cells in an animal (except gametes) have two sets of chromosomes. This means that animal cells have two homologous copies of each chromosome, usually one from the mother and one from the father. Such organisms are called diploids. Humans are also diploid organisms which means that they carry two complete sets of chromosomes: one set of 23 chromosomes from their father and one set of 23 chromosomes from their mother. The two sets combined provide a full complement of 46 chromosomes. The haploid cells are gametes (sperm or egg cells) which contain one set of chromosomes, in case of human 23.