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tyou143
What is the probability that, in an organism with a haploid number of 12, a sperm will be formed that contains all 12 chromosomes whose centromeres were derived from maternal homologs?
Most sperm cells in the animal kingdom are haploid so lets say that the normal organism is diploid (has 2*12= 24 chromosomes). When a sperm cell is formed, one chromosome of each chromosome pair is put into the sperm cell. Which makes it haploid and thus gives it 12 chromosomes. If you have 2 chromosomes which are divided, the chance of getting one of them is 50%. Now, if you have 12*2 chromosomes which are divided this means that if you want to get the fathers chromosome every time this 50% chance must have the same outcome 12 times in a row. This gives you the formula: 50%^12 (50%*50%*50%*50%*50%*50%*50%*50%*50%*50%*50%*50%*) or as it is easily calculated: 0.5^12 (In which 1 states it happens every time and 0.5 states it happens half of the times etc.) So the answer is; 0.5^12=2.4*10^-4 or: 0.00024 in other words 1/0.00024 gives us a chance of 1 in 4096