Understanding Mendelian genetic heredity

When a fruit fly of genotype Mm Nn Oo is mated to another fly of identical genotypes, what proportion of the progeny flies will be MM nn Oo? (Assume that the three genes are independent) (a) 1/2 (b) 1/8 (c) 3/8 (d) 1/32 (e) 1/64

Understanding Mendelian genetic heredity.

Consider the cross Aa Bb Cc Dd Ee x aa Bb cc Dd ee (a) What proportion of progeny will PHENOTYPICALLY resemble (1) the first parent (2) the second parent (3) either parent (4) neither parent? (b) What proportion of progeny will GENOTYPICALLY resemble (1) the first parent (2) the second parent (3) either parent (4) neither parent?

Understanding Mendelian heredity.

Consider two-child families in which the parents have been identified as carriers of an autosomal recessive gene by virtue of having at least one child with the phenotype. When the children of many such two-child families are totaled, what proportion of children in these families will show the phenotype? (Hint: The answer is NOT twenty five percent!)

Recombination in bacteria and in viruses that infect bacteria.

Four E. coli strains of genotype a+ b- are labeled 1,2,3 and 4. Four strains of genotype a- b+ are labeled 5,6,7, and 8. The two genotypes are mixed in all possible combinations and (after incubation) plated to determine the frequency of a+ b+ recombinants. The following results were obtained, where M = many recombinants, L = low numbers of recombinants, and O = no recombinants. -----1----2----3---4 ---------------------- 5--O-M--M--O 6--O---M--M--O 7--L----O--O--M 8--O---L-L---O On the basis of these results, assign a sex type (either Hfr, F+, or F-) to each of the strains.

Recombination in bacteria and in viruses that infect bacteria.

In E. coli, four Hfr strains donate the markers shown in the order given: strain 1---Q---W---D---M---T strain 2---A---X---P---T---M strain 3---B---N---C---A---X strain 4---B---Q---W---D---M All these Hfr strains are derived from the same F+ strain. What is the order of these markers on the circular chromosome of the original F+?