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Calculate the allelic frequency of S1 using the data below. Round answer to 2 decimal places.  Genotype Number S1S1 4 S1S2 38 S2S2 134

Sickle cell disese is a genetic blood disorder that is inherited in an autosomal recessive manner. If two heterozygous parents have a normal child, what is the probability the child is a carrier of the trait? Write answer as a percentage rounded to the nearest whole number. 

How can you repress gene expression without changing the DNA sequence?

Below are three statements. Which of the following choices properly matches the statements with the correct biological processes?

Two genes, A and B, are located 30 map units apart. AB/ab is crossed with ab/ab. What percentage of the offspring is expected to be AB/ab? 

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You are studying two linked genes in lizards. You have two females and you know that both are the same genotype, heterozygous for both genes (Aa and Bb). You testcross each female to a male that is fully homozygous recessive for both genes (aa and bb) and get the following progeny with the following phenotypes:                                              Female 1     Female 2                                               AB – 3          AB – 50                                               ab – 3           ab – 49                                               Ab – 45         Ab – 5                                               aB – 52         aB –3 How can you explain the drastic difference between these two crosses?

A mother with the genotype AaBbcc and a father with the genotype aaBbcc plan to have kids.  If each of these loci sort independently and follow typical patterns of Mendelian inheritance, what percentage of the offspring with have the same genotype as the mother?  Enter your answer as a percentage and round your answer to the nearest whole number. 

How does an XX female inherit her two sex chromosomes

Dr.Gantar is studying leopard gecko coloration.  She found three genes that appear to determine some coloration and are linked.  Based on the data below, the middle gene is .  st = stripes y = yellow patches sp = spots F1 Testcross Progeny Phenotype Number spotted (+ + sp) 613 striped, yellow (st y +) 611 yellow (+ y +) 231 striped, spotted (st + sp) 217 striped (st + +) 131 yellow, spotted (+ y sp) 125 striped, yellow, spotted (st y sp) 6 wildtype (+ + +) 7 Total 1941