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DNA, Chromosomes and the Genomes

Klinefelter Syndrome Synopsis

How is Klinefelter Syndrome Inherited? Klinefelter syndrome is a term used to describe men who are born with an extra X chromosome in the majority of their cells. The cells of a normal, healthy person contain two copies of each of 23 chromosomes, for a total of 46 chromosomes per cell. Everyone has two sex chromosomes. Males ha

Explanation of transcription and translation

The student asked for help understanding how to take a DNA sequence, transcribe it to mRNA and then translate it to amino acids. Detailed information is given to explain the steps one needs to take in order to accomplish both tasks. The assignment posted also asked about mutations, so an explanation of mutations is also provided

Alleles Sequence Causing Blue Soybeans

Suppose you are working for a biotechnology company in the "New Plant Products" division. You wander into the greenhouse and come across a recently harvested bag of soybeans that are colored a neon blue. There are currently 5 soybean plants in the greenhouse, but the bag is not labeled as to which plant they were obtained from

X-linked trait, autoradiograph

Mom Smith is heterozygous for an X-linked trait that can be recognized by a polymorphism when her DNA is cut with Hae III and probed with ExTend probe. The polymorphism is a 3.5kb band for normal and a 1.5kb band for disease. Please diagram what you predict the autoradiograph would look like for the above samples if th

Restriction enzyme fingerprinting is summarized.

BAC clones can also be ordered by restriction enzyme fingerprinting. A typical BAC may be around 200kb and EcoRI may cut on average roughly once every 4kb. Hence, a typical BAC EcoRI digest may contain 40-50 bands. The accuracy with which band sizes can be measured is very important for this type of mapping. It is likely bette

Genomic library

1. Imagine you have an ordered library of mouse genomic BAC clones (of roughly 200-250 kb each), named BAC-1, BAC-2 etc. ("1", "2" etc. in the table below). You also have a set of STS markers, named a, b, c, d etc. You are trying to order the clones by STS content mapping. The table below presents all of the BAC clones that i

Plasmid Transfer

You are trying to construct a plasmid to be transfected (introduced) into mouse tissue culture cells in order to find out whether a specific protein localizes to the nucleus or the cytoplasm. You have three purified plasmids as starting materials. The objective is to combine pieces of these plasmids to make one purified plasmid

ampicillin-resistant plasmid

You have a 4kb ampicillin-resistant plasmid with one BamHI site and a single HindIII site 1.5kb away from the BamHI site (shortest distance). you cut one microgram of the circular DNA (which we will assume has no nicks in it) with BamHI, and one microgram with HindIII. You heat-inactivate the enzymes (if you prefer you could

Transcription in Eukaryotes

1. a. What unit is considered to compose the first order of chromatin folding in eukaryotes? b. Define the terms "heterochromatin" and "euchromatin." c. Why is transcription control necessary in eukaryotes? 2. a. List the three types of RNA polymerase enzyme, and for each, give the RNA molecule type it produces. b. What

Genetic Testing and Disease

See the attached file. DNA screening Many corporations have started presenting at home DNA health screening. A person has a cheek swab that isolates DNA and it then evaluated for patterns investigative of disposition to disease, by of which a lot of these disorders are still yet to be curable. -What are a few disadvantag

Ancestry DNA Tests

I'd just like to know: 1) are ancestry dna tests(mtDNA,Y-chromosome STR test) reliable? 2) in the case of Y-chromosome test,as long as they analyse markers on the Y chromosome,does it give ancestry only on the father of my father of my father.... or on the whole of my father's side(and his father,mother,etc.) If it gives ances

The Difference between Eukkaryotic and Prokaryotic mRNA

Eukaryotic genes differ than prokaryotic genes. Please explain, in depth, the post-transcriptional modification that a eukaryotic mRNA goes through before it leaves the nucleus and how this differs from the transcriptional events in a prokaryotic system.

Explanation for chromosomal aberration in animals and plants.

What is the impact of chromosomal aberration during Meiosis II, when the normal gametes generated as an end product of Meiosis II are compared with those produced from Meiosis II with chromosomal aberrations? What would happen when an abnormal gamete is crossed with a normal gamete produced from the end product of MeiosisII?

Theories of Biology

Evolution by Natural Selection, Inheritance, Cells, Biological Classification, Bioenergetics, Homeostasis, and Ecosystems. Summarize each of the major theories above. Inheritance - How is this theory relevant in the news today?

Strain of Aspergillus was subjected to mutagenesis by X rays

A strain of Aspergillus was subjected to mutagenesis by X rays, and two tryptophan-requiring mutants ( A and B) were isolated. These tryptophan-requiring strains were plated in large numbers to obtain revertants to wild type. You failed to recover any revertants from mutants A and recovered one revertant from mutant B. This r

Western Blot

Please see attachment for image. You ran your experiments on a gel and detected the proteins using a Western Blot (again remind yourself how do you make recombinant proteins, generate antibodies, and perform a Western). You results are demonstrated on this gel. The lanes are designated with the letter A-G. Vertical lines are

Effects of Altered Status/Growth and Development on Disease Processes

3. Explain why teratogens are difficult to identify. 4. Explain why a woman carrying the gene for hemophilia can produce two hemophiliac sons when she is mated to a normal male. 5. Under what conditions does a female acquire an X-linked recessive disorder? 7. The pedigree for Queen Victoria of England, a carrier

Mule - Hybrid of Horse & Donkey

Please see attached file. 1. A stable polyploidy plant species was found that has 26 chromosomes, which form 13 bivalents in meiosis. Is it an autoploid or alloploid? 2. Horses have 64 chromosomes, while donkeys have 62. Hybrids between horses and donkeys are mules, and are sterile. If two mules mated, with each prod

What will be the phenotypes and proportions of the progeny?

In fruit flies, black body (b) is recessive to gray body (b+), purple eyes (pr) is recessive to red eyes (pr+), and vestigial wings (vg) are recessive to normal wings (vg+). The loci coding for these traits are linked, with the following map distances: b____5_____pr_______5_______vg The interference among these gen

Restriction enzymes

In the following sequence find restriction sites for EcoRI, HindIII and Hae III. Show how many fragments will be produced by restriction by all of these enzymes at the same time and their size, Which of the fragments produced will have 5'-overhang, 3'-overhang or blunt end? GAAGAACCTGAATTCAAATTTGGCCCTGCTGCTGAAGCTTGCTGACCAGG


1. What sequence of nucleotide pairs in a Drosophila gene will encode the amino acid sequence met-trp-phe-trp-met (reading from the amino terminus to the carboxyl terminus)? 2. A wild type gene contains the trinucleotide-pair sequence: was 5'-GAG-3' changed to:5'-GTG-3' 3'CTC -5' 3'-CAC-5' If the second base

Amino acids and nitrogen products

Although normal E.coli cells can synthesize all the amino acids, some mutants called amino acid auxotrophs, are unable to synthesize specific amino acids and require the addition of that amino acid to the culture medium for optimal growth. In addition to their role in protein synthesis, specific amino acids are also required in