Final answer:
A human gamete contains 23 chromosomes, which include autosomes and one sex chromosome. This haploid number ensures that upon fertilization, the zygote has the correct diploid number of chromosomes for development. The sex of the offspring is determined by the sex chromosome present in the gamete.
Step-by-step explanation:
The number of chromosomes in a human gamete is 23. This is because gametes are sex cells, such as sperm and eggs, that are produced through a process called meiosis. During meiosis, the chromosome number is halved, and thus each gamete receives one set of 23 chromosomes. Human somatic cells have a total of 46 chromosomes, arranged in 23 pairs, with one set of chromosomes inherited from each parent. Among these 23 pairs, 22 are autosomes and one pair is the sex chromosomes, which are either XX in females or XY in males. The reduction from 46 to 23 chromosomes in gametes is essential for sexual reproduction, ensuring that when two gametes combine (fertilization), the resulting zygote has the proper diploid number of chromosomes. The sex chromosomes in gametes are of special importance because they determine the sex of the future organism. Females contribute one X chromosome to the offspring, while males can contribute either an X or a Y chromosome. This genetic mechanism is what leads to the sexual differentiation in humans.