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biology aqa aslevel meiosis question

A scientist observed 300 cells. All of the cells were at exactly the same stage ofmeiosis as the cell shown in Figure 2.
https://filestore.aqa.org.uk/sample-papers-and-mark-schemes/2022/june/AQA-74012-QP-JUN22.PDF page 10
Use your knowledge of the independent segregation of homologous chromosomes to calculate how many of these cells are expected to have an identical arrangement of chromosomes to those shown in Figure 2. Assume no crossing over occurs.

ans is 18-19 but idk how
you can see there are 4 pairs of chromosomes. That gives 2^4 = 16 possible different sets of chromosomes. For any given pairing, such as the one in Figure 2, there's a 1/16 chance. Observing 300, you'd see 300/16 of any possible pairing. So it's 300/16 = 18.75.
Reply 2
Original post by Theloniouss
you can see there are 4 pairs of chromosomes. That gives 2^4 = 16 possible different sets of chromosomes. For any given pairing, such as the one in Figure 2, there's a 1/16 chance. Observing 300, you'd see 300/16 of any possible pairing. So it's 300/16 = 18.75.

thank you

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