Transmission Genetics

What is the probability of rolling two six-sided dice and obtaining an odd number on at least one die?

27/36 (look in notebook to find how to get the answer)

In peas, axial (A) flower position is dominant to terminal (a), tall (L) is dominant to short (l), and yellow (Y) is dominant to green (y). If a plant that is heterozygous for all three traits is allowed to self-fertilize, how many of the offspring would show the dominant phenotype for all three traits?

27/64

Determine the expected ratio of offspring phenotypes.

3:1

How many different gamete genotypes can the organism with genotype AABbCcAABbCc produce?

4

How many different gamete genotypes can the organism with genotype AaBbCCAaBbCC produce?

4

What is the probability that the children will be four girls and one boy?

5/32

What is the probability of rolling one six-sided die and obtaining any number but 6?

5/6

You count 1000 F2 seeds from a monohybrid cross. How many do you expect to display the dominant phenotype?

750

How many different combinations of alleles are possible among the gametes produced by an individual that is heterozygous for three separate genes?

8; For an individual with the genotype AaBbCc, the gametic combinations would be ABC, aBC, AbC, ABc, abC, aBc, Abc, and abc. Using the calculation 2n, where n = 3 heterozygous genes, the answer would be 2*2*2 = 8.

In some of Mendel's experiments, a cross in which one plant provides the pollen and another with the same genotype provides the egg is followed by another cross in which the first plant provides the egg while the second provides the pollen. During his experiments, these ________ crosses produced identical results.

Reciprocal

In Guinea pigs, short hair (S) is dominant over long hair (s), rough coat (R) is dominant over smooth coat (r), and black hair (B) is dominant over white hair (b). Which of the following individuals could produce these (and only these) four possible gametes: SRb, Srb, sRb, srb.

SsRrbb

Choose the correct description for the blending theory of heredity and how Mendel's results help to reject this theory.

The blending theory viewed the traits of progeny as a mixture of the characteristics possessed by the two parental forms. Mendel's results show no blending in individual traits and the blending theory was disproven.

A test cross between a heterozygous parent and a homozygous recessive parent is expected to produce a 1:1 genotypic and phenotypic ratio.

True

If a dihybrid F1F1 plant is self-fertilized, 9/16 of the progeny will have the same phenotype as the F1 parent.

True

The progeny of a trihybrid cross are expected to have one of 27 different genotypes.

True

One key to Mendel's success was choosing to observe ________ traits, which exhibit one of two possible phenotypes.

dichotomous

What simple type of cross that investigates the inheritance of only one trait could be used to illustrate Mendel's law of segregation?

monohybrid cross

For the cross aabbaabb×AaBb×AaBb , what is the expected genotype and phenotypic ratio?

1:1:1:1

What genotypic ratio would you expect to see among the progeny of a monohybrid cross?

1:2:1

Based on the law of segregation, what proportion of the F2 plants (which are in the ratio 1 RR : 2 Rr : 1 rr) would be expected to produce F3 progeny phenotypes in a ratio of 3 dominant : 1 recessive?

1/2

If three differently colored dice are rolled at the same time, what is the probability that a 6 will be the outcome on each one?

1/216

What is the probability of rolling one six-sided die and obtaining a 1 or a 2?

1/3

What is the probability of rolling two six-sided dice and obtaining two 4's?

1/36

In peas, axial (A) flower position is dominant to terminal (a), and tall (L) is dominant to short (l). If a plant that is heterozygous for both traits is allowed to self-fertilize, how many of the offspring would also be heterozygous for both traits?

1/4

If a plant with purple, axial flowers and green, inflated pods is heterozygous for all four genes, how many different types of gametes can it produce?

16

Based on Mendel's law of independent assortment, what phenotypic ratios are expected among the F2 progeny from a dihybrid cross?

9:3:3:1

The law of independent assortment predicts that crossing of dihybrid F1 plants to one another would produce nine genotypes in a ________ ratio among the F2 progeny.

9:3:3:1

Mendel's law of segregation predicts the following specific phenotypic ratios among the F1 and F2 progeny from crosses between two pure-breeding parents for a single trait (e.g., yellow vs. green peas).

F1 1:0 F2 3:1

If a dihybrid F1 plant is self-fertilized, 1/16 of the progeny will be true-breeding.

False

If a dihybrid F1 plant is self-fertilized, 1/2 of the progeny will be heterozygous at one or both loci.

False

If a dihybrid cross is performed, the expected genotypic ratio is 9:3:3:1.

False

If a woman is heterozygous for albinism, an autosomal recessive condition that results in the absence of skin pigment, the proportion of her gametes carrying the allele that allows pigment expression is expected to be 75%.

False

Reciprocal crosses that produce identical results demonstrate that a strain is pure-breeding.

False

The outcome of a trihybrid cross is predicted by the law of segregation.

False

A ratio of 9:3:3:1 is expected among the F2 progeny of a dihybrid cross as a result of ________ of alleles at two loci.

Independent Assortment

The gene L determines hair length in rabbits. The gene B determines hair color. A rabbit with long, black hair is crossed to a rabbit with short, white hair. All the offspring have long, black hair. What are the genotypes of the parents?

LLBB × llbb

Several features of Gregor Mendel's experiments on plant breeding and patterns of inheritance distinguished his work from that of his contemporaries. Which of the following was a critical experimental innovation employed by Mendel that distinguished his experiments from those of his contemporaries?

Mendel performed controlled crosses with pure-breeding strains.