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Mendel's Law and Genetics

How do you apply Mendel's law to solve this problem? You have three yellow, round peas, labeled I, II, and III, and each was grown into a plant and crossed to a plant grown from a green, wrinked pea. There were 100 peas issuing from each cross were sorted into phenotypic classes as shown below: I. 52 yellow, round

Schematic of the Lac Operon

See the attached file. Below is a schematic of the lac operon: SHAPE * MERGEFORMAT A special class of mutants of E coli unable to utilize lactose as a carbon source were found to have mutations in the coding sequence for β-galactosidase (lacZ gene). They produce no β-galactosidase protein. Surprisingly, they fail to

Punnett Squares and Genetics

1) Assume the gene for dimples, d, is recessive. Then assume that two individuals with the genotypes Dd and dd mate. Create a Punnett square for this mating and state the probability that their offspring will have dimples. 2) Briefly explain epistasis. 3) List the steps of mitosis and briefly describe what happens in each.

Seminal Fluid (DNA) Testing and Analysis

can any one do it in an hour..i need to learn... suggest credits 4..A prison guard states that an inmate threw and unknown liquid on him. This is a felony charge of harassment. In order for this charge to be prosecuted, you must show a bodily fluid was thrown on the guard. The shirt smells like vomit. How would you proceed?

Mendel's Law

Using Mendel's laws, describe the phenotypic and genotypic ratios for the F2 generation if pea plants with restricted yellow pods are crossed with restricted yellow pods and crossed with true-breeding inflated green pods in the original cross and then the F1 generation is crossed. I do not understand this at all. Please explain.

Genetics in everyday life

Genetics plays a great part in every day life these days. From solving crimes to determining the desirable properties of livestock and crops - science has made many advances. These days biotechnology enables us to have more control than was previously though possible. What do you think - should we be able to control the characte

Cancer And Genetic Predisposition

Both of Susie's parents died from breast cancer. Susie tested positive for the BRCA1 gene, the BRCA2 gene, and HPV; however, she does not have any cancer cells in her body or any signs or symptoms. Susie just called you and told you that she has decided to undergo a double radical mastectomy to remove both of her breasts and a c

Genotype Frequencies

In a human population of 1000 people at a blood locus there are two alleles M and N. The observed genotype frequencies at this locus are f(MM) = 0.26, f(MN) = 0.35, and f(NN) = 0.39. a. What is the frequency of each allele in this population? Do not assume Hardy-Weinberg equilibrium. b. Based on the answer above calculate

X-Linked Traits

1. Eye color is an X-linked gene and red is dominant to white in Drosophila. If I mate a red eyed male with a white eyed female and I mate a white eyed male with a pure breeding red eyed female, the progeny from both crosses will be the same. A. True B. False 2. Mary met her partner Bobby at a support group for families

Genetically modified organisms (GMO)

Pros and Cons of GMO Technology Pros: Genetically Modified Organisms(GMO) can benefit and contribute to medicine in many ways. For example, there are genetically modified microorganisms that can make human insulin to treat diabetic patients. (3) There are genetically modified bacteria that can be used to clean toxic fuel an

Lac Operon: State Of Transcription

The lac operon encodes a set of genes for the metabolism of lactose. There are three genes encode by the lac operon: lac Z gene, lac Y gene, and lac A gene. (1 ) The lac Z gene translate into B-galactosidase. (1) The lac Y gene translate into lactose permease. (1) The lac A gene translate into lactose transacetylase. (1) T

The major categories of cells, genes, mRNA, and autotrophs

Fill-in each blank with the appropriate word(s) to complete the sentences. There are two major categories of cells. These categories are _______________ cells, which include bacteria, and __________________, which include fungi. ____________________ is the term that describes an organism's ability to maintain a stable intern

Is Venomousness Determined by a Sex-Linked Trait?

1. What happens when you step on a nail? 2. What happens when you breathe in a virus? 3. If female vampires are venomous, male vampires are venomous, and Nahuel (a Male hybrid vampire) is venomous, why are all known female vampire hybrids not venomous? Is being venomous a sex-linked trait or a coincidence based on other chromo

cell genetics and genetic information

1. How do the base pairing relationships of DNA bases account for the uniform width of the double helix? 2. Look at Figure 13.13a-c on page 552 on the textbook. What enables the two DNA polymerase III molecules to act on replication as a unit (i.e., simultaneously replicating the leading and lagging strands) even though they

Heritable traits: stem length and number in orchid plants

An orchid breeder is interested in increasing the number of stems and the length of stems that can be produced by an orchid plant. She finds a segregating population that contains a wide range of both stem number (Ranging from 2 to15 stems per plant) and stem length (Ranging from 2 to 7 inches in length). She selected plants fro

Types of mutations that could occur in a proto-oncogene gene

The following list are several types of mutations that could occur in a proto-oncogene or a tumor-suppressor gene. Some of these mutations may increase the rate of progression through the cell cycle (Thus promoting cancer), whereas others would either decrease the rate or have no effect. For each of the below scenarios, writ

Identifying Prototrophic Revertants

The Ames test is used to determine if an external agent (such as a chemical) can act as a mutagen. In this test, several different his- strains of Salmonella typhimurium are used. Each strain contains a different class of mutation in the his gene. Each mutant is exposed to the chemical to determine if the chemical can revert the

Determining Genotypes in DNA Test

Tay-Sachs disease is a fatal, recessively heritable, delayed onset illness that develops during infancy. In a certain community, a widespread mutant allele for Tay-Sachs disease removes a Hind III restriction site in the gene sequence. A probe is available for this region, with the following homology:


The autoradiogram below shows the genomic DNA fragments produced by digesting genomic DNA with the restriction enzyme Mst II and probing the membrane with a DNA probe specific for the beta globin chain gene of hemoglobin. The parents are C and D, and the children are E and F. Hb S indicates a mutated gene leading to the sickle

Exons and Introns

A human gene was initially identified as having three exons and two introns. The exons are 456, 224, and 524 bp, while the introns are 2.3 kb and 4.6 kb. (a) Draw the gene, showing promoter, 5' UTR, 3' UTR, introns, exons. (b) Surprisingly, it is found that this gene encodes not one but two mRNAs that have only 224 nucleoti

Functional Effect of Gene Mutations

Suggest the likely gene function mutated in each of the following defects during replication in E. coli (a) Accumulation of Okazaki fragments. (b) The presence of RNA in newly synthesized DNA strand. (c) Many mismatched base pairs. (d) DNA replication does not initiate

Biosynthetic Pathways in Mutations

You have isolated four different mutants unable to synthesize compound E required for growth. You know that compounds A through D are involved in the biosynthetic pathway that produces compound E, but you do not know the order in which they are synthesized by a wild-type cell. You supplement the growth of each of the 4 mutant

Contain Genes Regulate Conjugations

The following table contains statements pertaining to Hfr, F+, F', and/or F- strains of bacteria. Indicate in respective boxes if the statements apply to each category by putting Hfr, F+, F', F- beside the statement. a) Contains genes that regulate conjugation and the transfe

Cross breeding

Vanessa has obtained two true-breeding strains of mice, each homozygous for an independently discovered recessive mutation that prevents the formation of hair on the body. The discoverer of one of the mutant strains calls his mutation "naked," and the other researcher calls her strain "hairless." To determine whether the two

brown eyeBrown and blue eyes genotypess vs blue

Genetically speaking, brown eyes (B-) are dominant to blue eyes (bb). However, an individual can wear colored contacts in order to change his or her eye phenotype. Suppose a man with blue eyes (bb) marries a woman who appears to have blue eyes and together they have five children. Listed below are three possible outcomes. Gi

Pedigree Inheritance Pattern

Four patterns of inheritance and four pedigrees are shown below. Assume that individuals marrying into the family are homozygous for the wild-type allele. Match each of the inheritance patterns with a pedigree. (a) Autosomal recessive _________ (b) Y-linked trait _________ (c) X-linked recessive _________ (d) Autosomal domi

Pedigree Inheritance Pattern of Huntington's Disease

Please see attachment for pedigree inheritance pattern of Huntington's disease. Huntington's disease is a late-onset disease caused by a single, dominant mutation. The following pedigree is for a family with a history of Huntington disease. Those individuals who are already suffering from the disease are shaded black. However

biosynthetic pathway

The production of the purple pigment anthocyanin in flowers is accomplished via a biosynthetic pathway. A biosynthetic pathway consists of a series of enzymatic reactions resulting in the creation of a final end product via several intermediate metabolites. An example of a biosynthetic pathway is shown below: S