What did Alfred Hershey and Martha Chase do?
Starting in 1951, Alfred Hershey and Martha Chase conducted a series of experiments, later called the Hershey-Chase experiments, that verified the findings of Avery and his colleagues. Hershey was a researcher who studied viruses at the Carnegie Institution of Washington in Cold Spring Harbor, New York.
Who is Alfred Hershey?
Alfred Day Hershey (December 4, 1908 – May 22, 1997) was an American Nobel Prize –winning bacteriologist and geneticist .
What is Martha Chase best known for?
Martha Cowles Chase (November 30, 1927 – August 8, 2003), also known as Martha C. Epstein, was an American geneticist who in 1952, with Alfred Hershey, experimentally helped to confirm that DNA rather than protein is the genetic material of life. Chase was born in 1927 in Cleveland, Ohio.
What did Alfred Hershey do in the Hershey experiment?
Alfred Hershey. He moved with his research partner Martha Chase to Laurel Hollow, New York, in 1950 to join the Carnegie Institution of Washington 's Department of Genetics, where he and Martha Chase performed the famous Hershey–Chase experiment in 1952. This experiment provided additional evidence that DNA, not protein,...
What was used by Hershey and Chase in their experiments?
Hershey and Chase ExperimentContent: Hershey and Chase ExperimentDefinition of Hershey and Chase Experiment. Hershey and Chase’s experiment has dem...
What results did Hershey and Chase experiment observe?
In their experiments, Hershey and Chase showed that when bacteriophages, which are composed of DNA and protein, infect bacteria, their DNA enters t...
What did Alfred Hershey and Martha Chase discover?
Through a series of experiments the duo conducted in 1952, Alfred Hershey and Martha Chase discovered that genetic material is found in DNA. Prior...
What is the summary of the Hershey and Chase experiment?
There are two batches.One batch (Batch 1) had phages that were grown with radioactive sulfur that was incorporated into the phage protein (inside t...
Who was Alfred Hershey?
Biography 18: Alfred Day Hershey (1908-1997) Alfred Hershey was a phage geneticist who, with his research assistant, Martha Chase, did one of the most famous experiments in molecular biology. The "blender" experiment proved that DNA carried genetic information.
What did Hershey and Chase prove?
Hershey and Chase and subsequent discoveries all served to prove that DNA is the hereditary material.
Where did Hershey and Chase conduct their experiments?
In 1951 and 1952, Alfred Hershey and Martha Chase conducted a series of experiments at the Carnegie Institute of Washington in Cold Spring Harbor, New York, that verified genes were made of deoxyribonucleic acid, or DNA.
How did Hershey and Chase label phage DNA?
One may also ask, how did Hershey and Chase label phage DNA? Hershey and Chase used T2 phage, a bacteriophage. The phage infects a bacterium by attaching to it and injecting its genetic material into it. They labeled the phage DNA with radioactive Phosphorus-32 . They then followed the phages while they infected E.
Who was Alfred Hershey?
Alfred Hershey was a phage geneticist who, with his research assistant, Martha Chase, did one of the most famous experiments in molecular biology. The "blender" experiment proved that DNA carried genetic information.
Who worked with bacterial genetics?
Joshua Lederberg worked with bacterial genetics while Alfred Hershey showed that DNA is responsible for the reproduction of new viruses in a cell.
What were the two things Hershey and Chase used to determine the genetic material of a virus?
Hershey and Chase already knew that viruses were composed mainly of DNA and protein; however, they did not know if DNA or protein was the genetic material. Hershey and Chase used radioisotopes to mark the DNA and protein. They used the radioactive isotopes phosphorus and sulfur because DNA contains phosphorus and proteins contain sulfur. Using these radioactive isotopes gave them the ability to distinguish between the DNA and the protein.
What type of bacteria did Griffith work with?
Griffith worked with two different strains of Streptococcus pneumonia, a type S strain, and a type R strain. Type S bacteria were characterized by the existence of a polysaccharide, which allowed them to evade being attacked by the host cell's immune system; however, type R bacteria did not have such a polysaccharide capsule. Griffith injected type S bacteria into the mice. Due to the existence of the polysaccharide capsule, the type S bacteria were able to thrive in the mouse's blood stream. Therefore, the mouse died. Afterwards, Griffith injected type R bacteria into mice.
Did Griffith know the genetic material of the bacteria?
Evidently, the type R bacteria had developed genetic material from the heat-killed type S bacteria; however, Griffith did not know what the genetic material was. Meselson and Stahl conducted experiments to determine whether or not DNA followed the semiconservative, conservative, or dispersive model of replication. The semiconservative model states that the two daughter molecules each consist of one old strand, from the parent, and one newly constructed strand.
Who was Alfred Hershey?
Alfred Hershey was a phage geneticist who, with his research assistant, Martha Chase, did one of the most famous experiments in molecular biology. The "blender" experiment proved that DNA carried genetic information. ID: 16419. Source: DNAFTB.
Who worked with bacterial genetics?
Joshua Lederberg worked with bacterial genetics while Alfred Hershey showed that DNA is responsible for the reproduction of new viruses in a cell. 16409. Gallery 18: Alfred Hershey, 1969. Alfred Hershey receiving the 1969 Nobel Prize in Physiology or Medicine.
Who is Alfred Hershey?
Washington University Medical School. Alfred Day Hershey (December 4, 1908 – May 22, 1997) was an American Nobel Prize –winning bacteriologist and geneticist . He was born in Owosso, Michigan and received his B.S. in chemistry at Michigan State University in 1930 and his Ph.D. in bacteriology in 1934, taking a position shortly thereafter at ...
Where did Hershey Chase and Martha Chase live?
He moved with his research partner Martha Chase to Laurel Hollow, New York, in 1950 to join the Carnegie Institution of Washington ' s Department of Genetics, where he and Martha Chase performed the famous Hershey–Chase experiment in 1952.
How many children did Hershey have?
Hershey had one child, Peter Manning Hershey (1956-1999) with his wife Harriet (often called Jill) (1918-2000). The family was active in the social network of Cold Spring Harbor Laboratory and regularly enjoyed the beach in season. Hershey was a Christian .
Who was the leader of the Phage Church?
After Hershey died, another phage worker, Frank Stahl, wrote: "The Phage Church, as we were sometimes called (see Phage group ), was led by the Trinity of Delbrück, Luria, and Hershey. Delbrück's status as founder and his ex cathedra manner made him the pope, of course, and Luria was the hard-working, socially sensitive priest-confessor. And Al (Hershey) was the saint."
What did Hershey Chase discover?
The experiment involved radioactively labeling either protein or nucleic acid of the bacteriophage T2 (a virus that infects bacteria) and seeing which component entered E coli upon infection. They found that nucleic acids but not protein were transferred, helping resolve controversy over the composition of hereditary information. Hershey won the Nobel Prize in Physiology or Medicine for the discovery in 1969, but Chase was not included.
Where was Chase born?
Chase was born in 1927 in Cleveland, Ohio. Her father was a Western Reserve University Science Instructor and she grew up with her family in Cleveland Heights, Ohio. After graduating from Cleveland Heights High School, she received a bachelor's degree from the College of Wooster in 1950, then worked as a research assistant before returning to school in 1959 and receiving a PhD in Microbiology from the University of Southern California in 1964.
What is the Chaseviridae family?
The family Chaseviridae, a group of bacteriophages in order Caudovirales, was named in honor of Martha Chase.
Did Martha Chase divorce Richard Epstein?
Epstein. The marriage was brief and they divorced shortly after with no children. A series of personal setbacks through the 1960s ended her career in science.
Did Martha Chase have children?
Epstein. The marriage was brief and they divorced shortly after with no children . A series of personal setbacks through the 1960s ended her career in science. She moved back to Ohio to live with family and spent the last decades of her life suffering from a form of dementia that robbed her of short-term memory. She died of pneumonia on August 8, 2003, at the age of 75.
Overview
The Hershey–Chase experiments were a series of experiments conducted in 1952 by Alfred Hershey and Martha Chase that helped to confirm that DNA is genetic material.
While DNA had been known to biologists since 1869, many scientists still assumed at the time that proteins carried the information for inheritance becau…
Historical background
In the early twentieth century, biologists thought that proteins carried genetic information. This was based on the belief that proteins were more complex than DNA. Phoebus Levene's influential "tetranucleotide hypothesis", which incorrectly proposed that DNA was a repeating set of identical nucleotides, supported this conclusion. The results of the Avery–MacLeod–McCarty experiment, published in 1944, suggested that DNA was the genetic material, but there was still some hesitat…
Methods and results
Hershey and Chase needed to be able to examine different parts of the phages they were studying separately, so they needed to distinguish the phage subsections. Viruses were known to be composed of a protein shell and DNA, so they chose to uniquely label each with a different elemental isotope. This allowed each to be observed and analyzed separately. Since phosphorus is co…
Discussion
Hershey and Chase concluded that protein was not likely to be the hereditary genetic material. However, they did not make any conclusions regarding the specific function of DNA as hereditary material, and only said that it must have some undefined role.
Confirmation and clarity came a year later in 1953, when James D. Watson and Francis Crick correctly hypothesized, in their journal article "Molecular Structure of Nucleic Acids: A Structure …
Legacy
The Hershey–Chase experiment, its predecessors, such as the Avery–MacLeod–McCarty experiment, and successors served to unequivocally establish that hereditary information was carried by DNA. This finding has numerous applications in forensic science, crime investigation and genealogy. It provided the background knowledge for further applications in DNA forensics, where DNA fingerprinting uses data originating from DNA, not protein sources, to deduce genetic variati…
External links
• Hershey–Chase experiment animation
• Clear depiction and simple summary