1.) How many versions (alleles) of a gene can we carry if every chromosome is in pair?
2) What happens during the gamete formation (meiosis) ? Do the gene pairs stay together?
3) What happens then to the paternal and maternal sets of genes that we inherited ?
1) I think that it could be any number, but confused with 2 as an answer.
2) Gene pairs must refer to homologous chromosome pairs which remain together in meiosis-I and get separated in meiosis-II. So in net process, it get separated.
3) It is used for producing proteins essential for body functioning by the process of transcription and translation. These genes with some changes (due to crossover) will also be transferred to second generation.