If organism has 18 chromosomes in its body cells. Its sex cells have 9 chromosomes then Its sex cells are haploid and a result of meiosis.
Humans are diploid, and most of the body's cells contain 23 chromosomes pairs. Human gametes (egg and sperm cells), however, contain a single set of chromosomes and are said to be haploid.
Humans contains 23 pairs of chromosomes, that makes a total of 46. 22 of these pairs are called autosomes, look the same in both males and females.
Gametes are haploid cells that contain 23 chromosomes, each of which a one of a chromosome pair that exists in diploid cells.
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