Exam 3: Mendelian Genetics

Which types of phenotypic ratios are likely to occur in crosses when dealing with three gene pairs for which all the genotypic combinations are of equal viability?

Albinism,lack of pigmentation in humans,results from an autosomal recessive gene a .Two parents with normal pigmentation have an albino child.What is the probability that their next child will be an albino girl?

Under what conditions does one expect a 1:1:1:1 ratio?

A cross between two individuals with different phenotypes that resulted in approximately 50% of each type of offspring would indicate the cross was__________ .

Mendel's Law of Segregation is supported by a __________ testcross ratio.

Under what conditions does one expect a 9:3:3:1 ratio?

In a Chi- square analysis,what general condition causes one to reject fail to accept the null hypothesis?

Assuming complete dominance,a phenotypic ratio of __________is expected from a monohybrid sib or self- cross.

Mendel crossed two pea plants with round seeds.All seeds of the offspring were round.He then crossed a plant with round seeds to a plant with wrinkled seeds and all offspring had wrinkled seeds.Which of the following is true?

Tightly curled hair is caused by a dominant autosomal gene in humans.If a heterozygous curly- haired person marries a person with straight hair,what phenotypes and in what proportions are expected in the offspring?

Two organisms,AABBCCDDEE and aabbccddee.,are mated to produce an F1 that is self- fertilized.If the capital letters represent dominant,independently assorting alleles.How many different genotypes will occur in the F2?

Name the single individual whose work in the mid- 1800s contributed to our understanding of the particulate nature of inheritance as well as the basic genetic transmission patterns.With what organism did this person work?

Assume that you have a garden and some pea plants have solid leaves and others have striped leaves.You conduct a series of crosses [a)through e)] and obtain the results given in the table.Define gene symbols and give the possible genotypes of the parents of cross E.

What meiotic process,relative to the number of chromosomes of a given species,accounts for a significant amount of genetic variation in gametes?

The autosomal not X- linked gene for brachydactyly,short fingers,is dominant to normal finger length.Assume that a female with brachydactyly in the heterozygous condition is married to a man with normal fingers.What is the probability that their first child will be a brachydactylous girl?

Assuming independent assortment,what proportion of the offspring of the cross AaBbCcDd × AabbCCdd will have the aabbccdd genotype?

Tightly curled or wooly hair is caused by a dominant gene in humans.If a heterozygous curly- haired person marries a person with straight hair,what percentage of their offspring would be expected to have straight hair?

According to Charles Darwin and Alfred Wallace,variations followed a more continuous pattern.According to Mendel's model,variation due to dominance- recessive relationships followed a more __________ form.

If an F2 generation from a self- cross always yields offspring in a 3:1 phenotypic ratio,which of the following P crosses could have occurred?

You have identified a plant in your garden with a new flower color.You want to determine if this phenotype is dominant or recessive.Which cross would tell you this?