Question

which of the following is true of an organism that has a chromosome number of 2n = 16?
○ during the s phase of the cell cycle, there will be 32 separate chromosomes.
○ the species has 16 sets of chromosomes per cell.
○ each cell has eight homologous pairs of chromosomes.
○ a gamete from this species has four chromosomes.

Explanation:

• During the S phase: DNA replication occurs, but chromosomes are still attached at the centromere (sister chromatids), so chromosome number remains \(2n = 16\).
• Sets of chromosomes: \(2n\) means diploid, so there are 2 sets of chromosomes per cell.
• Homologous pairs: If \(2n=16\), then \(n = 8\). The number of homologous pairs is equal to \(n\), so there are 8 homologous pairs.
• Gamete chromosome number: Gametes are haploid (\(n\)). If \(2n = 16\), then \(n=8\), so a gamete has 8 chromosomes.

Answer:

Each cell has eight homologous pairs of chromosomes.