Gametes have a) homologous chromosomes b) twice the number of chromosomes found in body cells c) two sets of chromosomes d) one allele for each gene

D

Explanation:

Gametes, also called sex cells, are reproductive cells produced during meiosis for reproduction purposes. Gametes, due to their formation by meiosis, contains half the number of chromosomes as the organisms producing them.

Gregor Mendel, who established certain principles governing the passing of traits to offsprings called inheritance, performed experiments that illustrated that each gamete receives one form of a gene i.e. allele. Mendel discovered that each organism receives two forms of gene (allele) from each parent. These alleles (variant form of a gene) separate into gametes during meiosis in a way that each gamete has only one allele of a gene.

For example, a plant with genotype Tt (N.B: T and t are alleles of the gene coding for height) will undergo meiosis and its alleles T and t will separate into gametes in equal proportion I.e. one gamete will contain T allele while the other gamete, t allele.

After food has been chewed and lubricated, the tongue the pushes it into the pharynx, also known as the throat. From there it travels into the esophagus. Once in the esophagus, the muscles work to push it down in the stomach. The mouth is the first stop in the complete digestion process.