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    Expected genotype and phenotype ratios

    Assume a gene for warped wings (W) in Drosophila that is dominant and X-linked. give the expected genotype ratios and phenotype ratios for the progeny of each of the following crosses: a)warped male x normal female b)warped heterozygous female x normal male c)warped heterozygous female x warped male

    Offspring phenotypes

    In guinea pigs, dark coat color (C) is dominant over albino (c), and short hair (S) is dominant over long hair (s). The genes for these two traits show independent assortment. By evaluating the possible crosses, determine the most probable genotypes for the parents of each of these seven crosses: parental phenotypes

    Corn Kernel Genotypes and Phenotypes

    A) While examining an ear of corn, you notice that the kernels in the ear display two apparent phenotypes; yellow and white. inspired by your understanding that these represent different alleles of a single gene, you count the kernels of each type and you asses 347 yellow (Y) kernels and 111 white (y) kernels. if this ear of c


    In humans, the ability to taste PTC is inherited as a dominant gene (T; Taster). in a marriage between two heterozygous tasters (Tt): a) what is the probability of 3 taster children? b)what is the probability of 3 taster girls? c)if they have 5 children, what is the probability that the first 3 will be tasters and the last

    % of traits passed to progeny

    The average pea pod contains about 7 peas. The gene for smooth peas is dominant over the gene for wrinkled peas. If heterozygous pea pods grown from smooth peas are self-fertilized and all of the pods have 7 peas, what percentage of the pods will have: a) all smooth peas? b) 5 smooth and 2 wrinkled peas?


    Describe a single gene inherited disease, a multi-factorial (multiple genes and environmental factors) disease, and non-inherited genetic disease. Use Down syndrome, sickle-cell anemia, asthma and breast cancer as examples


    What is parental imprinting? What is the result of replacing the sperm nucleus of a fertilized egg with another egg nucleus?

    Genetic probabilities

    49% of the population has a particular gene. A test has been developed that can determine if a person has this gene or not. The test has a false positive (says the person has the gene when they don't) rate of 6%, and a false negative rate of 3%. What is the probability that a random person will test positive to having this gene


    Vinblastine is a drug that interferes with the assembly of microtubules. It is widely used for chemotherapy in treating cancer patients whose cancer cells are actively dividing to form tumors. Suggest a hypothesis to explain how vinblastine slows tumor growth. Assuming that albinism is under the control of a si

    Phobias, Alzheimer's Disease & Memory

    #1 Phobias Introduction: Your best friend has just called you with some great news! The president of the company that your friend works for has asked your friend to make a speech at the next stockholder's meeting. When you congratulate your friend, however, your friend tells you that a terrible fear of public speaking may

    Debates: Deception, Male and Female Brain & Stem Cell Debate

    #1 When Is a Lie Not a Lie? The issue of some psychological research using deception in order to gather information. This is often done in social psychology experiments where it is necessary to "set up" a situation in order to study individuals' responses. At the conclusion of the study, participants are always told the tr

    Plant Biotechnology and Oak Domestication

    You are a geneticist working for a firm that specializes in plant biotechnology. Explain what specific parts (fruit, seeds, stems, roots, etc.) of the following plants you would try to alter by genetic engineering, what changes you would try to make, and why, on a) corn, b) tomatoes, c) wheat, and d) avocados. Only a few

    Genetically Altered Foods are overviewed.

    Nowdays lots of food that get on our table are genetically altered. Some people are not bothered by that fact. Some demand more facts supporting that such foods are safe to eat and will not bring any negative alterations to our health later. The effects of GM foods are noted.

    Life on earth (biological concepts from the non-science major perspective)

    1. When comparing the DNA molecule to a twisted ladder, what do the rungs of the ladder represent? 2. Describe the three major properties of genes that are explained by the structure of DNA? 3. What occurs on the sex chromosomes to determine the sex of a mammal? 4. Describe a difference between meiosis and mitosis?

    biological concepts from the non-science major perspective

    Hemophilia is a sex-linked trait in humans. That means that the gene that is responsible for it resides on the X chromosome. Hemophilia is a hereditary disorder characterized by the failure of the blood to clot properly. As a result, such individuals suffer from excessive bleeding. Sometimes it results in death. Here are th

    A Hardy Weinberg inquiry is solved.

    In a population that is in Hardy-Weinberg equilibrium, 16% of the population shows a recessive trait. What is the frequency of the dominant allele (p) in the population?

    Flower color in carnations

    Flower color in carnations is controlled by one pair of co-dominant alleles; red flowered carnations have the genotype RR, white flowered carnations have the genotype R'R', and heterozygous individuals are pink. Of 10,000 plants in a carnation population that is in Hardy-Weinberg equilibrium, 4900 plants possess red flowers. H

    Hardy Weinberg Problem

    Assume that left-handedness is a recessive trait controlled by one pair of dominant-recessive alleles. If 625 of 2,500 individuals in a sample of a population is left-handed, and if the population is in Hardy-Weinberg equilibrium, how many individuals in the entire population of 10,000 would be predicted to be heterozygous for

    A Hardy Weinberg flower problem is solved.

    Carnations exhibit "blended inheritance" (co-dominant or intermediate inheritance). 2 alleles for color R and R' produce red and white flowers, respectively, when in homozygous condition. When an individual possesses bothe alleles (RR') their phenotype is pink. If the allele frequency for R is 0.23, how many pink individuals

    Hardy-Weinberg Populations

    A population of rattlesnakes lives on a desert island. Some members of this population have a unique adaptation which protects them form parasites that reside in the sand. The allele for this special adaptation is recessive. You count all the snakes on the island and find that there are 120 snakes, 42 of which do not have th

    Hardy Weinberg Law

    In a population of field mice, 3 phenotypes: black, brown, and white are observed. Upon investigating, you discover that 2 alleles cause the 3 phenotypes (alleles B and B' are co-dominant). The allele for black coat color is B and the allele for white coat color is B'. Thus, individuals with the genotype BB are black, B'B' a