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Genetics

Constructing pedigrees to analyze and determine inheritability and probability.

Gaucher disease is caused by a chronic enzyme deficiency that is more common among Ashkenazi Jews than in the general population. A Jewish man has a sister afflicted with the disease. His parents and grandparents, and other three siblings are not affected. Discussions with his relatives in his wife's family reveal that the disea

Mendelian Genetic problems

Could you please take a look at the attached problems that I have done which include Punnett square and genotype. I think I have done the problems correctly but I just need a second set eyes to see if there are any holes in my understanding on this topic.

Calculating phenotypic ratio in dihybrid crosses

In garden peas, yellow seed color is dominant over green, and round seed shape dominant over wrinkled. What phenotypic ratio can be expected in F2 from a cross between pure yellow and round with green and wrinkled? What would be the ratio of yellow: green and round: wrinkled? Ideas are included.

Probability in genetics is the feature topic.

If two heterozygous brown rabbits are crossed, what would be the probability of the first three baby rabbits being brown, white, brown or white, brown, white? Explanations are included.

Understanding eukaryotic chromosome mapping techniques.

In haploid yeast, a cross between arg- ad- nic+ leu+ and arg+ ad+ nic- leu- produces haploid sexual spores, and 20 of these are isolated at random. The resulting cultures are tested on various media as shown below (in the table below, + means growth, while - means no growth). (a) What can you say about the linkage arrangement

Understanding Recombination in Bacteria.

A transformation experiment is performed with a donor strain that is resistant to four drugs: A, B, C, D. The recipient is sensitive to all four drugs. The treated recipient-cell population is divided up and plated on media containing various combinations of the drugs. The results are shown in the table below. Drug # co

Potential problems with transgenic mouse strains.

You have created 3 independent mouse strains carrying the same transgene by non-targeted transgenesis. All 3 strains have otherwise identical genetic backgrounds, yet all 3 have different phenotypes. What are potential explanations for this phenotypic variability?

Genetics -- map units

EDIT to the problem below: I just realized that the various numbers of offspring add up to 9900, not 10,000, which is the supposed total. So for problem #2, I randomly added 100 to my recombinant numbers and got the answer, 30.1, which turned out to be correct. But the same thing did not work for problem #1. Adding 100 to the

Double Cross-overs

Hi. Can you help me with the following genetics problem, please: "Consider a pair of homologous chromosomes heterozygous for three genes (e.g., ABC/abc) during prophase I of meiosis. Let the sister chromatids of one homolog be numbered 1 and 2 (ABC); and the sister chromatids of the other homolog be numbered 3 and 4 (abc).

Family Pedigree and Cystic Fibrosis

Your sister has cystic fibrosis and you are contemplating having children of your own. Your mate recalls having a cousin with the disease. What is the risk that one or more of your children will have cystic fibrosis? If you can draw a pedigree of your family, assuming you have only one sister and your mate has only one sister.

Punnett Square for Mendelian Genetics

"a" is a dominant mutant allele of the A gene, and "b" is the recessive mutant allele of the B gene. To see the mutant phenotype, one requires either an "a" mutant phenotype or a "b" mutant phenotype (both mutations are not necessary). What would the F2 segregation ratio be (wild type to mutant) of the cross of an aabb mutant

F1 and F2 generations: aa bb (mutant) x AA BB

You cross an aa bb mutant plant with an AA BB wild type. What would the F2 segregation ratio be (wild type to mutant) if: a.) both mutations, a and b, were recessive? b.) both mutations were dominant? c.) one mutation was dominant and one recessive? (assume both mutations are required for the mutant phenotype) (assume t

The Hardy-Weinberg law states two things:

Background The Hardy-Weinberg law states two things: 1. If no outside forces are acting on the population, then the allele frequency will remain constant from one generation to the next. 2. If no outside forces are acting on the population, then the genotype frequencies will be p^2, 2pq, and q^2. The converses of these sta

Understanding the Hardy-Weinberg equation is achieved.

Which of the following statements is true? The Hardy-Weinberg equation provides a way to: Predict the response to a solution for a quantitative tract Determine the degree of drift affecting a population Calculate test credibility Predict genotype frequencies of given alleles Predict episodes of proverbial equilib

Mutation Characteristics of the Gene that Codes for CAK

Of the genes that code for CAK, wee1, and cdc25, which would you expect, when mutated, to stop a cell from continuing to divide? Which would you expect, when mutated, to cause the cell to proliferate in an uncontrolled manner?

Factors Involved When Genetically Modifying A Mouse

Suppose you are given the task of genetically modifying a mouse so that its skin cells secrete a bitter tasting protein that will protect it from predation. What factors would you have to consider in order to achieve this goal? You only need to consider protein targeting, do not be concerned with how you would get the gene int

Probability genes

Assume that a trait is determined by a single pair of genes where one allele is dominant and the other is recessive. In a population, 30% of the females are pure dominant, 60% are hybrid, and 10% are pure recessive. If a pure recessive male mates with a random female and their first offspring has the dominant trait, what is th

Understanding BRCA genes, related to human breast cancer.

Using the NCBI website resources find information related to BRCA genes, related to human breast cancers. Use "locus link" at http://www.ncbi.nlm.nih.gov/ (Tutorials are available if you get stuck) 1) find the chromosomal position of the BRCA-1 gene 2) what is another gene located next to BRCA-1 at this chromosome 3

The Different Phases of Meiosis

If a child more strongly resembles one parent's physical traits than the other parent's, the explantion could be due to chromosome movements during? A. anaphase II B. metaphase II C. prophase II D. anaphase I E. telophase I This study is discussed.

Breeding Dihybrid Crosses

In cocker spaniels, black coat color (B) is dominant over red (b), and solid color (S) is dominant over spotted (s). If two dihybrids (Bb Ss) were crossed, which would be produced? A. black and spotted pure-breeding forms B. black and solid pure-breeding forms C. red and solid pure-breeding forms D. red and spotted pu