Explore BrainMass

DNA, Chromosomes and the Genomes

Human biology - mRNA

This sequence of bases is found in a section of bacterial mRNA.The codon shown on the left hand end of the sequence is the start codon for this gene. AUGUUUGCUGGGGGACAUUCGUGGGCA from your knowledge of base-pairing rules deduce the sequence of bases in the DNA template strand from which this mRNA was transcrib


Suppose the (1) ____ oocyte is on its way down an oviduct when a female and male are engaged in sexual intercourse, or (2) _____. The male sex act requires (3) _____________ and ejaculation. During coitus, pelvic thrusts stimulate the penis, the female's (4) ____________, and the vaginal wall. The mechanical stimulation induces


FSH and (1) _______ stimulate cells outside the zona pellucida to secrete (2) _____. A(n) estrogen-containing fluid accumulates in the follicle, and estrogen levels in the blood begin to increase. About eight to ten hours before being released from the ovary, the (3) _____ completes Meiosis I. And then its (4) _____ divides, for

Protein degradation

In addition to protein phosphorylation and dephosphorylation, protein degradation also plays key role in regulating signal transduction pathways and cell proliferation. Please answer the following questions: (1). Please give one example to describe how protein degradation regulates signal transduction pathway; (2) Plea

Monomeric receptors

Why can't a monomeric receptor tyrosine kinase recruit proteins to the receptor? What would happen if the GTP-ASE protein(GAP) were inhibited? EDIT: I have found the answer to the the second question posted here. However, I believe I have discovered the answer to the first question, but I fail to understand it. Can someone


If the G protein alpha subunit has a mutation so that it can't hydrolyze GTP, what happens?. If the G-protein can only bind to GDP how would that effect the pathway? I believe if the alpha subunit has a mutation and cant hydrolyze GTP then the G-protein will be unable to inactivate itself. How will this be bad?

Molecular switches

Someone with knowledge about GEF's and GAP's please help me understand what this means. In the regulation of molecular switches, protein kinases and guanine nucleotide exchange factors(GEF's) turn proteins on and protein phosphotases and GTPase activating proteins(GAP's) turn proteins off.

Protein expression / Pulse-chase

I want to study a human protein(protein X) that is normally secreted from the cell. I express the gene for Protein X in cultured Rat cells. I conduct a pulse-chase experiment in which I specifically label Protein X(and no other cellular protein) at 37 degrees celcius and then perform a 35 minute chase also at 37 degrees celcius

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

I have a major question about the hereditary genes. Using Mendelian genetics you can determine the likelihood of your eye color, your hair color, some things that fall in these lines, but at the age of 25 I would like to know how I can determine when I will have a head full of white hair. My father has some white hair and my


A man has genotype AA, Bb, cc, DD, ee, FF. what would be the genotypes of any and all sperm he might produce considering all six genes

Phenotypic ratios

What phenotypic ratio would be expected in offspring from a cross of Aa CC x aa CC if gene "a" and gene "c" were independent and A = long hair, a = short hair, C = brown coat, and c = white coat


A geneticist determines that long hair length in mink is dominant over short hair (recessive). his friend breeds mink in captivity with long hair esp for the fur inducstry and has received permission from the Kansas Department of Wildlife and Parks to trap 5 wild mink to add to his breeding stock to reduce effects of inbreeding

Phenotypes are predicted.

A man who has free earlobes marries a woman who has attached earlobes. What would be the expected phenotypes ( and ratios or percentages) of off spring if the man were homozygous? Assume E= dominant allele for free earlobes and e - recessive allele for attached earlobess. Ideas are included.

DNA Structure & Function

In given a polypeptide that is composed of five amino acids: methionine-valine-glutamic acid-lysine-tyrosine. What is the mRNA sequence, the complementary DNA sequence, and the tRNA anticodons of( *See Attached Chart*) Please include the STOP codon.

Genetic Cross

A) Cross a wildtype female with a yellow bodied male to produce an f1 offspring generation. Which allele is domonant and which is recessive. Justify your responce using your results. b) Now mate F1 individuals to produce an F2 generation. report the results and explain them. Is there evidence of sex linkage. justify your respon

Usefulness of the test cross

We have to attach all of the sources. I am having trouble finding anything but examples and biology teacher notes. I have worked on this for 2 days and only have an opening statement that seems to pretty much sum up everything. I need to avoid unnecessary information but I feel I have limited resources. Can someone please el

Insertion in DNA

Bacterial mRNA AUGUUUGCUGGGGGACAUUCGUGGGCA produced the following template strand from which this mRNA was transcribed TACAAACCACCCCCTGTAAGCACCCGT My questiohn is inserted a T at the begining of the sequence to produce TTACAAACGACCCCCTGTAAGCACCCGT what is the new mRNA sequence corresponding with this altered DNA Deletetion of th

Likages are explored.

In Aspergillus, the genes y (yellow), os (osmotic), c (colonial), leu (leucine-requiring), and a (aconidial) are located on the long arm of chromosome 3. A diploid was made between a haploid wild type and a haploid of genotype y os c leu a. From the green diploid, yellow diploid sectors appeared. When these were sampled and test

What is the Polymerase Chain Reaction?

The Polymerase Chain Reaction (PCR), devised by Kary Mullis in the mid-1980's has revolutionized molecular biology by allowing a whole new approach to the study and analysis of genes. i) What is PCR? ii) What are the steps involved? iii) What are the necessary reagents involved in making the PCR work?