After allowing phages grown with bacteria in a medium that contained 32P and 35S, Hershey and Chase used a centrifuge to separate the phage ghosts from the infected cell. They then examined the infected cells and found that they contained _____, which demonstrated that _____ is the phage's genetic material.
labeled DNA, DNA
In a DNA double helix an adenine of one strand always pairs with a(n) _____ of the complementary strand, and a guanine of one strand always pairs with a(n) _____ of the complementary strand.
After DNA replication is completed, _____.
each new DNA double helix consists of one old DNA strand and one new DNA strand
Why is the new DNA strand complementary to the 5' to 3' strands assembled in short segments?
DNA polymerase can assemble DNA only in the 5' to 3' direction
The synthesis of a new strand begins with the synthesis of a(n) _____.
RNA primer complementary to a preexisting DNA strand
Which of the following statements about DNA synthesis is true?
Primers are short sequences that allow the initiation of DNA synthesis.
Which part of a deoxynucleoside triphosphate (dNTP) molecule provides the energy for DNA synthesis?
Which of the following statements about Okazaki fragments in E. coli is true?
They are formed on the lagging strand of DNA.
Which of the following enzymes is important for relieving the tension in a helix as it unwinds during DNA synthesis?
True or false? Single-stranded DNA molecules are said to be antiparallel when they are lined up next to each other but oriented in opposite directions.
Which of these is a difference between a DNA and an RNA molecule?
DNA is double-stranded, whereas RNA is single-stranded.
In a nucleotide, the nitrogenous base is attached to the sugar's _____ carbon and the phosphate group is attached to the sugar's _____ carbon.
The researchers used strands of DNA located at the ends of chromosomes (called telomeres) to classify the cells they studied. What assumption did they make about telomeres?
Longer telomeres indicate younger cells.
The research showed that individuals who _______ had younger looking cells based on telomere measurements.
exercised for an average of 30 minutes per day
Which of the following is true?
Overall, the nuclear accident at Fukushima was not as bad as the accident at Chernobyl.
You were exposed to 4 millisieverts of radiation last year. That is ______ times the maximum recommended by the International Commission on Radiological Protection.
Members of what organization collected samples that have indicated high radiation levels in Tokyo?
Radiation Defense Project