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Genetics

Imprinted Gene

Imagine that for a maternally imprinted gene, allele a encodes an inactive version and allele A is the wildtype version. Do you expect the following individuals to exhibit an abnormal phenotype? Why or why not? a) a female of genotype Aa in which the wildtype allele came from her father? b) a male of genotype Aa in which the wil

Encoding a protein with a pair of conflicting signal sequences

Imagine you have engineered a set of genes, each encoding a protein with a pair of conflicting signal sequences that specify different compartments. If the genes wer expressed in a cell, predict which signal would win out for the following combinations. Explain. a. Signals for import into the nucleus and import into the ER

Biology problems

1. A species of wren arrives on a chain of volcanic islands off the coast of New Zealand that previously had no wrens. After several thousand years, wrens from these islands are able to interbreed with occasional migrants from the mainland, but the resulting offspring are poorly adapted to compete with the local wrens and produc

Gene linkage

Eye color in Drosophila depends on the synthesis of two pigments, a red pigment and a brown pigment, resulting in the wild-type (WT) dull red eye color. Mutations blocking production of the brown pigment result in bright red eyes, while mutations blocking production of the red pigment result in brown eyes. If both pathways are

GENE duplication

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

Genotypes

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

Grandchildless

1. You have isolated a recessive Drosophila mutant that you call grandchildless (gls) because it behaves in the following way: Cross: gls/gls female x +/+ male F1: All sterile If you perform the reciprocal cross, however, you find that the result is different from that in cross 1: Cross: gls/gls male x +/+ female

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

1. Duchene 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 ave

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

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 Question

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 dete

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

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

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.

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

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

Plant Crosses

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

Complementation

You are handed six yeast strains: three strains (a, b, c) have a defect in the LEU1 complementation group, the other three (d, e, f) have defects in the LEU4 complementation group (LEU being an abbreviation for leucine). if you plate diploid cells, created from mating the haploid strains together, on a minimal media plate with

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

Determining the mode of inheritance and gene linkage for drosophila crosses...

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 conclusions about link

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

Generation of Diversity

Explain the purpose (and briefly the method) of generating a TCR transgenic mouse ? Why TCR transgenic mice are often made on a rag-/- background ?

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

Genetics

1) In a tetrad analysis of a new ascomyete, you are observing a difference in phenotype between spores- some haploid spores are shaped like a square/cube (S) while other spores are round (r). when a square-spored strain is crossed with a round-spored strain, you observe 698 asci with the pattern (SSSSrrrr), 245 asci with the pa

Probability - A woman of blood type A and normal color vision...

A woman of blood type A and normal color vision produced five children as follows: a)male, blood type A, color blind b)male, blood type O, color blind c)female, type A, color blind d)female, type B, normal vision e)female, type A, normal vision of the two men that mated with this woman at different times, man #1 is blo