Molecular Genetics Test

what is a label

14N and 15N

Based on Chargaff's rules, the percentage of cytosine in the DNA of the bacterium S Lutea should be around

26.6%

If a DNA sample contains 13% adenine, what percentage of the sample contains cytosine?

37%

DNA pol I removes the primer from ________ end of the 2nd fragment replacing it with DNA nucleotides that it adds one by one to the 3' end of the 3rd fragment. The replacement of the last RNA nucleotide with DNA leaves the sugar-phosphate backbone with a free 3' end.

5'

At a specific area os a chromosome the following sequence of nucleotides is present where the chain opens to form a replication fork, 3' CCTAGGCTGCAATCC 5' An RNA primer is formed starting at the underlined T of the template. Which represents the primer sequence?

5' ACGUUAGG 3'

The leading strand is synthesized continuously in the ____________

5' to 3' direction by DNA pol III

how did Avery's experiment build on griffith's findings

Avery found the transformation factor in the experiment but didn't know what it was

A space probe returns with a culture of microorganism found on a distant planet. Analysis shows that it is carbon based life form that has DNA. You grow the cells in 15N medium for several generations and then transfer them to 14N medium. Which tube would you find if the DNA was replicated in a conservative manner.

B

In trying to determine whether DNA or protein is the genetic material, Hershey and Chase made use of what fact

DNA contains phosphorus, whereas protein does not

how did the hershey-chase experiment provide evidence that nucleic acids not protein are the hereditary material

DNA is a nucleic acid and that is considered the hereditary material so it wouldn't be proteins

what assumptions were made about the role of DNA in viruses and bacterial and the role of DNA in eukaryotes

DNA is the only material transferred directly from the phage to bacteria when it is infected

______ ______ bonds the 3' end of the 2nd fragment to the 5' end of the 1st fragment

DNA ligase

What enzyme removes the RNA nucleotides from the primer and adds equivalent DNA nucleotides to the 3' end of Okazaki fragments

DNA polymerase I

which enzyme catalyzes the elongation of a DNA strand in the 5' to 3' direction

DNA polymerase III

A new DNA strand elongates only in the 5' to 3' direction because

DNA polymerase can only add nucleotides to the free 3' end

what did Avery's experimental results show

DNA was the transformation factor

DNA was shown to be the transforming substance when only the _____________ enzymes could inhibit transformation

DNAase

What investigator was responsible for the following discovery? In DNA from any species, the amount of adenine equals the amount of thymine, and the amount of guanine equals the amount of cytosine

Erwin Chargaff

what was Griffith's experiment

His experiment tested mice and pneumonia. He gave mice either rough or smooth strands of the virus, and sometimes heat killed the sample of the virus. He found that when he put live rough virus and heat killed smooth, the rough transferred its genetic material to the smooth one.

Who conducted the pulse-chase experiment

Matthew Meselson and Franklin Stahl

What was the Hershey-Chase experiment?

Phosphorus labeled core(DNA) and sulfur labeled cap (protein)

What is not true about DNA replication

Replication occurs as each base pairs are held together with hydrogen bonds

what is meant by the description "antiparallel" regarding the strands that make up DNA

The 5' to 3' direction of one strand runs counter to the 5' to 3' direction of the other strand

What was the Avery-MacLeod-McCarty Experiment

They tested each component of heat killed S cells separately as they inserted them into R cells to find the Transforming Principle

what do bacteriophages infect

bacteria

What property of DNA does bacterial transformation illustrate?

bacterial DNA can move into another bacteria and function

what is the pulse

cells that are exposed to a label compound

what will the tubes look like for a conservative replication

dark and light (gen 0 is dark)

Primase begins synthesis of RNA primer for ____________

fifth Okazaki fragment

DNA pol III is completing synthesis of the ______ _______ when it reaches the RNA primer on the third fragment it will dissociate move to the replication fork, and add DNA nucleotides to the 3' end of the fifth fragment primer

fourth fragment

griffith did not predict transformation in his experiment, what results was he expecting

he was expecting once the cells were dead nothing would happen, but then the transformation factor occurred

What enzyme separates the DNA strands during replication

helicase

Nucleotides do not contain what

histones

What is the role of DNA ligase in the elongation of the lagging strand during DNA replication

it joins Okazaki fragments together

DNA replication is considered semiconservative because

it uses the original stand as a template for replication

what will the tubes for dispersive replication look like

light on top (gen 0 is only dark)

what will the tubes look like for a semiconservative replication

light on top with a hybrid below it (dark is only at gen 0)

Which bacteria killed the mice in Griffith's transformation experiment?

live, harmless bacteria and heat-killed, harmful bacteria

what is inside a bacteriophage

nucleic acid

Rosalind Franklin contributed to the understanding of DNA by

producing images of DNA molecules using X-rays

Replication in prokaryotes differs from replication in eukaryotes for what reason

prokaryotic chromosomes have a single origin of replication whereas eukaryotic chromosomes have many

What is the function of topoisomerase

relieving strain in the DNA ahead of the replication fork

What helps hold the DNA strands apart while they are being replicated

single-strand binding proteins

in the hershey-chase experiment what happened to the bacteria that had been infected by the viruses that had radioactive DNA and to the bacteria that had been infected with viruses that had been marked with radioactive proteins

the bacteria infected with viruses that had radioactive DNA had become radioactive. The bacteria that had been infected with the viruses marked with radioactive proteins were not radioactive

how would the results of the experiment have differed if proteins carried the genetic information

the genetic information would be stored in a different place

Griffith called the process he observed transformation because

the harmless bacteria had been transformed

The leading and the lagging strands differ in that

the leading strand is synthesized in the same direction as the movement of replication fork, and the lagging strand is synthesized in the opposite direction

What happened when Griffith injected mice with the harmless, R-strain bacteria alone?

the mouse lived

what is the chase

the unlabeled form replaces the labeled compound

Molecules of single-strand binding protein stabilize ________

the unwound template strands

Griffith's experiments advanced the study of genetics by proving that

there is a chemical that contains genetic information that can be passes from one organism to the other

what is a pulse-chase experiment

two-phase technique used to examine cellular processes that take place over a period of time

Helicase _________________

unwinds the parental double helix