Which statement explains the difference in chromosomes in fruit fly (2n=4)? O Diploid cells have 2 chromosomes and haploid cells have 4 chromosomes.
O Fruit fly gametes have 2 chromosomes while parent cells have 4 chromosomes.
O Male gametes have 2 chromosomes and female gametes have 4 chromosomes.
O Some fruit fly parent cells have 2 chromosomes and others have 4 chromosomes.

O Fruit fly gametes have 2 chromosomes while parent cells have 4 chromosomes.

Explanation:

The fruit fly is a diploid (2n) species with a chromosome number equal to 4, which means that somatic cells have two sets of homologous chromosomes, each set composed of two chromosomes (2n = 4). Moreover, fly gametes are haploid (n) cells, containing each a complete set of two non-homologous chromosomes (i.e., half the amount of DNA compared to parent cells). During meiosis, a single cell divides twice following one complete round of DNA replication, producing thus four gametes with a haploid number of chromosomes.

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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