Question

PROBABILITY 5) In human beings, the absence of molars is inherited as a dominant trait. If two heterozygotes have four children, what is the probability that a.) all will have no molars? b.) three will have no molars and one will have molars? c.) the first two will have molars and the second two will have no molars? 1) Assuming a 1:1 sex ratio, what is the probability that five children produced by the same parents will consist of a.) three daughters and two sons? b.) alternating sexes, starting with a son? c.) alternating sexes? d.) all daughters? e.) all the same sex? f) at least four daughters? g.) a daughter as the eldest child and a son as the youngest? Galactosemia is inherited as a tecessive trait. If two normal heterozygotes produce children, what is the chance that a.) one of four children will be affected? b.) three children will be bom in this order normal boy, affected girl, affected boy? 6) 2) Phenylthiocarbamide (PTC) tasting is dominant (T) to nontasting (). If a taster woman with a nontaster father produces children with a taster man, and the man previously had a nontaster daughter, what would be the probability that a.) their first child would be a nontaster? b.) their first child would be a nontaster girl? c.) if they had six children, they would have two nontaster sons, two nontaster daughters, and two taster sons? d.) their fourth child would be a taster daughter? STATISTICS 7) Mendel self-fertilized pea plants with round and yellow peas. In the next generation he recovered the following numbers of peas 315 round and yellow peas 108 round and green peas 101 wrinkled and yellow peas 32 wrinkled and green peas a) What is your hypothesis about the genetic control of the phenotype? Do the data support this hypothesis? 3) On the average, about one child in every ten thousand live births in the United States has Two curly-winged flies, when mated, produce sixty-one curly and thirty-five straight-winged progeny. Use a chi-square test to determine whether these numbers fit a 3:1 ratio 8) phenylketonuria (PKU). What is the probability that a.) the next child born in a Boston hospital will have PKU? b.) after that child with PKU is born, the next child born will have PKU? c.) two children born in a row will have PKU? A short winged, dark-bodied fly is crossed 9) with a long-winged, tan-bodied fly. All the Fi progeny are long-winged and tin-bodied. F, flies are crossed among themselves to yield 84 long-winged, tan-bodied flies: 27 long-winged dark-bodied flies: 35 short- winged, tan-bodied flies; and 14 short- winged, dark-bodied flies 4) PKU and albinism are two autosomal recessive disorders, unlinked in human beings. If two people, each heterozygous for both traits, produce a child, what is the chance of them having a child with a.) PKU? b.) either PKU or albinism? c.) both traits? What ratio do you expect in the progeny? Use the chi-square test to evaluate your a) b) hypothesis. Is the observed ratio within the expected range?

Answer 1

Answer 1:-

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