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Genetics

GENE Duplication for Evolutionary Mechanisms

Gene duplication is an important evolutionary mechanism and, as result , many cases are known where species has two nearly identical genes.ySuppose there are two genes, A and B , that specify production of the same enzyme. An abnormal phenotype results only if an individual does not make any of that enzyme. What ratio of normal

Genotype Symbols for Zucchinis

You cross two true breeding strains of zucchini, one with green fruit and the other with yellow. The F1 plants are all green , but when these are crossed, the F2 plants consists of 9 green and 7 yellow. How many genes are involved in determining the zucchini color? Using your own symbols, designate which genotypes yield green an

Complete dominance

In rabbits, C= agouti coat color, c ^ch=chinchilla, c^h=Himalyan, and c=albino. The four alleles constitute multiple allelic series with complete dominance as follows: the agouti C is dominant to the three other alleles , c is recessive to all other alleles, and chinchilla is dominant to Himalayan. Determine the phenotype of pro

A recessive mutation in the human genome...

1. A recessive mutation in the human genome results in a condition called anhidrotic ectodermal dysplasia, which is associated with an absence of sweat glands. The condition can be detected by studies of the electrical conductivity of the skin, because skin without sweat glands has a lower electrical conductivity (higher resist

Hfr strains

In E.coli, four streptomycin-sensitive, prototrophic Hfr strains were mated with a stretomycin-resistant F^- strain auxotrophic for a number of nutritonal requirements. Matings were interrupted at various intervals, and cells were plated on streptomycin-containing minimal meduim supplemented with particular nutrients to test for

Genetics Questions on Duchenne Muscular Dystrophy

1. Duchenne muscular dystrophy (DMD) is due to an X-linked recessive gene. A.Explain why 8 to 10 % of female carriers of the DMD gene have muscle weakness. B. A Female carrier of DMD marries a phenotypically normal man. (i) Given the genotypes of the parents using appropriate genetic symbols. Female____ Male_____ (ii) On av

Single gene cross: Line A is a true-breeding line of brown mice. Line B is a true-breeding line of white mice. A male from line A is crossed to a female from line B. The resulting F1 offspring are all black. The F2 offspring have black, white, and brown mice. What type of interaction between genes is this?

4. Line A is a true-breeding line of brown mice. Line B is a true-breeding line of white mice. A male from line A is crossed to a female from line B. The resulting F1 offspring are all black. The F2 offspring have black, white, and brown mice. What type of interaction between genes is this? What proportion of sperm from t

Determining Blood Types

A man with type A blood marries a woman with type B blood. Their first child has type O blood. What proportion of his sperm have the IA allele? ______________ What proportion of her eggs have the IB allele? ______________ What is the chance that their second child will also have type O blood? Diagram this cross:

Practice problems

1. You're working on golden rice, a plant that promises to alleviate nutritional deficiencies in some developing countries. You cross two true breeding plants. One parent is has fat grains, wavy leaves, red flowers and is short in stature, while the other parent expresses the contrasting phenotypes of thin grains, straight le

Genetic Questions

1. In Burmese cats, brown coat color is dominant to tan coat. Brown coat is a highly prized trait in Burmese. You have a brown male cat that you would like to offer as a stud; therefore, you need to know if it is homozygous or heterozygous for brown coat color. A. Why is this important? B.Diagram a testcross that would det

Genetic Engineering

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 hun

Meiosis & Sexual Reproduction

1. First, define Meiosis. Then, define and discuss the "cost of meiosis" (Be sure to list at least 2 references in a References section. 2. Second, speculate on why sexual reproduction has evolved.

Sex-Linked Traits on Genes Located

The hemophilia gene is located 12 map units from the red-green colorblindness gene on the X chromosome. Red-green colorblindness is recessive to normal colorvision. A woman with normal blood clotting and normal color vision, but whose father was a hemophiliac and whose mother was red-green colorblind, marries a man who is not a

Four basic genetics problems

Practice problems 1. You're working in a lab that studies a particularly gruesome parasite from the Amazon that infests people's ear canals while they sleep. This parasite has a diploid number of 12 chromosomes in its somatic cells, consisting of 6 homologous pairs (i.e. 6 maternal and 6 paternal chromosomes). Another stud

Antibiotic Resistance

The evolution of antibiotic resistance in bacterial populations is a direct consequence of natural selection applied by widespread use of antibiotic drugs. When a new antibiotic is first introduced, it kills the vast majority of bacteria exposed to it. The surviving bacterial cells, however, may include individuals whose genomes

How would you try to alter by genetic engineering the following.

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 hun

Why defendant genes should be considered

I am thinking polygenic behaviors? I am trying to find reason why genetics is important important aspect in human behavior such as criminal behavior..maybe child molestation for example.

Ethical considerations of genetics

I am trying to figure out why a defendant's genes should be considered as a factor in the criminal behavior? Can you help me figure out some pointers and factors?

AP Bio genetics problem

In mice, long tails (L) are dominant to short tails (l). Straight whiskers (S) are dominant to curved (s). The genes are unlinked. Two mice are bed many times. The following is a compilation of the F1 data from each mating. 40 long tail, straight whisker 16 long tail, curved whisker 45 short tails, straight whiske

Can further evolution of antibiotic resistance can or cannot be prevented.

The evolution of antibiotic resistance in bacterial populations is a direct consequence of natural selection applied by widespread use of antibiotic drugs. When a new antibiotic is first introduced, it kills the vast majority of bacteria exposed to it. The surviving bacterial cells, however, may include individuals whose genomes

How to Set Up Dihybrid and Sex-Linked Crosses (Punnett)

How to set up the crosses... I know you take the genotype and set them up in a box but where specifically do the traits go? On a sex link trait question I know that the Y chromosome has nothing to mask it because it is shorter than the X chromosome so do you just leave that genotype off the cross?

You are a geneticist working for a firm that specializes in plant biotechnology

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 hundr

Mutation rates

The basic formula for mutation rate is: mutation rate= # mutation events/(gene x generation). consider a situation when a scientist measures the mutation rate in an organism over several generations. if the scientist observes 10 mutant organisms for a particular gene after 4 generations (assuming 100,000 individuals or 100,00

Using data to solve a genetics problem involving polygenes.

A cross between two inbred plants that had mean seed weights of 20 and 40 grams, respectively, produced an F1 generation with seeds weighing an average of 30 grams each. an F1 x F1 cross produced 1000 plants: 3 had seeds weighing 20 grams, 5 had seeds weighing 40 grams, and the others produced seeds with weights varying between

Mendel Genetics Problems

Please see attached word document. --- Assignment Part I - Mendelian Genetics (7.5 pts). Information on the analysis of crosses and Chi-square statistics are available under the supplemental reading section of the course website. Below is the Chi-square probability table at 0.05 (5%) Degrees of Freedom Reject the null

The Mode of Inheritance and Gene Linkage for Drosophila

See the attached file. 7. Conclusion and discussion sections: a. how many genes are involved in creating the eye pigment (based on the provided data). Mode of inheritance - are the genes autosomal or sex-linked and why, recessive or dominant and why, and are some genes linked and why. b. Hypothesis statement based on conc

Help needed

AP Bio: Preparation of Human Chromosome Spreads- Kit 4 1. Specify the location and function of the centromere. 2. a) Name the three types of chromosomes found in human cells based on the location of the centromere. b) Which type is not found in human cells? 3. Why is it necessary to expose the cells to hypotonic solut

DNA Questions

A. Biotechnology cannot be used to: ___________ a. Produce large quantities of particular human proteins. b. Produce effective and safe vaccines. c. Identify human fetuses with particular genetic diseases. d. Alter food plants to increase yield. e. Alter the intelligence levels of newborn infants. B. For these

Evolutionary Preservation of Certain Signaling Pathways

I need some help for coming up with some reasons as to why certain cell signaling pathways are preserved in species over the course of evolution. Why would natural selection favor a certain basic, primitive pathway when more advanced pathways have been developed in higher organisms? For example, a particular wound-healing p

MEIOSIS

Please answer the attached questions about meiosis (attached). --- LAB 10-A 1- With respect to the number of chromosomes, compare interphase of mitosis to interkinesis (between division I and II) of meiosis. 2- Which cell division process (meiosis I, Meiosis II, mitosis, or some combination) corresponds to the following