Exam 2: Transmission Genetics

Geneticists must be able to compare the outcomes they obtain in their experiments to the outcomes that might be expected to occur. Which test would they use to confirm that the difference between observed and expected outcomes could be attributed to chance?

The statistical interpretation of a chi- square value is determined by identifying the________ .

Humans have a gene, T, that is involved in muscle formation of the tongue. Individuals homozygous for one allele can roll their tongues, while individuals homozygous for the other allele cannot. If both parents can roll their tongues, but their child cannot, what can be said about the mode of inheritance?

By convention, when an OBSERVED experimental outcome has a probability of occurrence of less than 5% (<0.05), the experimental results are considered to be _______.

What are Mendel's first and second laws of inheritance, and what do they state?

What phenotypic ratio would you expect as a result of a test cross between two individuals where one that is homozygous recessive for alleles at two independent loci?

In mice, black coat color is dominant to white coat color. In the pedigree below, mice with a black coat are represented by darkened symbols, and those with white coats are shown as open symbols. What is the probability that I- 1, I- 2, II- 2, AND III- 1 are all heterozygous?

In Guinea pigs, short hair (S) is dominant over long hair (s), rough coat (R) is dominant over smooth coat (r), and hair (B) is dominant over white hair (b). List all the different possible gametes that can be produced by each of th individuals below. a. SSRRbb b. ssRrBB c. SsRrbb d. SsRrBb

In a cross between individuals who are both heterozygous (carriers) for a recessive disease, such as albinism, you would like to determine the risk of one or more children inheriting the recessive phenotype.________ probability can be used to calculate the probability of a particular combination of events that each have two alternative outcomes?

A cross between a short pea plant and a tall pea plant results in a 1:1 genotypic AND phenotypic ratio in the offspring. What are the genotypes of the parent plants?

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

In peas, the smooth allele is dominant over the wrinkled allele. A plant with round peas was crossed to a plant with wrinkled peas and all of the resulting plants had smooth peas. What are the genotypes of the parents in this cross?

Describe the traits that make Pisum sativum an ideal organism for genetic studies.

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

Why did Mendel cut off the nascent anthers during the process of artificial cross- fertilization?

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?

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

The genes responsible for some of the traits that Mendel observed have been recently identified and have helped in determining how molecular variation produces morphologic variation in pea plants. Allelic variation in the Sbe1 gene, which produces starch- branching enzyme 1, is responsible for which trait in peas?

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

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?