Accounting
Anthropology
Archaeology
Art History
Banking
Biology & Life Science
Business
Business Communication
Business Development
Business Ethics
Business Law
Chemistry
Communication
Computer Science
Counseling
Criminal Law
Curriculum & Instruction
Design
Earth Science
Economic
Education
Engineering
Finance
History & Theory
Humanities
Human Resource
International Business
Investments & Securities
Journalism
Law
Management
Marketing
Medicine
Medicine & Health Science
Nursing
Philosophy
Physic
Psychology
Real Estate
Science
Social Science
Sociology
Special Education
Speech
Visual Arts
Question
Assume that you grew a culture of E. coli for many generations in medium containing 15N (from the ammonium ion), a heavy isotope of nitrogen. You extract DNA from a portion of the culture and determine its density to be 1.723 gm/cm3 (call this sample A). You then wash the remaining E. coli cells and grow them for one generation in 14N, extract the DNA from a portion of the culture, and determine its density to be 1.715 gm/cm3 (call this sample B). You let the culture grow for one more generation in 14N, and extract the DNA (call this sample C). Each sample of DNA (A, B, and C) is then heated to completely denature the double-stranded structures, cooled quickly (to keep the strands separate), and subjected to ultracentrifugation. Present the centrifugation profiles for heat-denatured DNA (samples A, B, and C) that you would expect. Use the graph below. (Note: Although not the case, assume that single-stranded DNA has the same density as double-stranded DNA.)
Answer
This answer is hidden. It contains 0 characters.
Related questions
Q:
What is meant by the term heritability? Describe the components of heritability and provide a brief explanation of each. Of what interest is heritability to animal and plant breeders?
Q:
What are the name and formula for describing sample variability?
Q:
Given the following numbers, calculate the mean: 10, 12, 14, 16, 18.
Q:
What is the term given to a random subset of individuals who are selected for measurement in a particular study?
Q:
Provide a brief description of discontinuous inheritance and continuous inheritance. How are the two related? How are they different?
Q:
The 9:3:3:1 ratio is typical of a dihybrid cross in which complete dominance and independent assortment occur. What is the dihybrid ratio with independent assortment of polygenes?
Q:
Characteristics exhibited by continuously varying traits include ________.
A) sex-linked genes only
B) autosomal genes only
C) quantification by measuring, weighing, counting, etc.
D) a 9:3:3:1 ratio
E) 3:1 and 1:1 ratios
Q:
Briefly describe what is meant by the term edible vaccine.
Q:
The Genetic Testing Registry is designed to restrict public access to a variety of genetic processes.
Q:
How are gene therapy and recombinant DNA technology related?
Q:
A term often used to describe an organism that is a genetic mosaic, resulting from the introduction of DNA from another organism, is ________.
Q:
Typically, bacterial DNA contains less repetitive DNA than eukaryotic DNA.
Q:
The genomic organization of all living creatures is identical.
Q:
The terms proteomics and genomics mean essentially the same thing.
Q:
Explain the goal of the emerging discipline called systems biology.
Q:
A number of generalizations can be made about the organization of protein-coding genes in bacterial chromosomes. First, the gene density is very high, averaging about ________.
Q:
How are pseudogenes formed?
Q:
Present an overview of the gene organization in large-genome plants.
Q:
Intron frequency varies considerably among eukaryotes. Provide a general comparison of intron frequencies in yeast and humans. What about intron size?
Q:
One major difference between prokaryotic and eukaryotic genes is that eukaryotic genes can contain internal sequences, called ________, that get removed in the mature message.
Q:
What is meant by the term pseudogene?
Q:
The term paralog is often used in conjunction with discussions of hemoglobin genes. What does this term mean, and how does it apply to hemoglobin genes?
Q:
What is one major limitation of two-dimensional gel electrophoresis (2-DGE)?
A) It is extremely costly to execute in a typical molecular biology laboratory.
B) When products are separated, they tend to leach out of the gel matrix.
C) Only the most abundant products are detected.
D) 2-DGE can be run only on nucleic acids.
E) 2-DGE is useful only in separating eukaryotic gene products.
Q:
The human genome contains approximately 20,000 protein-coding genes, yet it has the capacity to produce several hundred thousand gene products. What can account for the vast difference in gene number and product number?
A) Alternative splicing occurs.
B) There are more introns than exons.
C) There are more exons than introns.
D) Much of the DNA is in the form of trinucleotide repeats, thus allowing multiple start sites for different genes.
E) Every gene can be read in both directions, and each gene can have inversions and translocations.
Q:
Numerous scientists around the world have proposed to sequence 10,000 vertebrate genomes in five years. What is the name of this plan?
A) Genome 10K
B) Bigger Than Life Plan
C) 10K or Bust
D) Vertebrate Beginnings
E) Vertebrate Enlightenment
Q:
A knockout animal, in the context of recombinant DNA technology, is one that has been completely anesthetized.
Q:
Reverse transcriptase is often used as the heat-stable enzyme in PCR.
Q:
A restriction map provides the location of sites cleaved by restriction enzymes.
Q:
What method might be used to study a knockout mouse that, by virtue of the lost gene or genes, generates a lethal condition?
Q:
What is a popular approach that is often used to introduce the targeting vector into cells?