chapter 16 Flashcards
who conducted the x ray diffraction studies that were key to the discovery of the structure of DNA?
franklin
DNA replication is said to be semiconservatice, which of the following statements correctly explains what this means.
each new double helix consists of one old and one new strand.
what are the repetitive DNA sequences present at the ends of eukaryotic chromosomes called?
telomeres
what process repairs damage to a preexisting double helix?
nucleotide excision repair
what are chromosomes made of
DNA and protein
which of the following is true of DNA during interphase?
it exists as chromatin and is less condensed than mitotic chromosomes.
when thomas hunt morgan crossed red eyed F1 generation flies to each other, the F2 generation included both red and white eyed flies, but all the white eyed flies were male, which of these best explains morgans results
the gene involved is located on the X chromosome
which of the following statements correctly describes the chromosome theory of inheritance as it was understood in the early 20th century.
mendelian genes are at a specific loci on the chromosome, and in turn, segregate during meiosis
frederick griffith heat killed a culture of pathogenic bacteria. he split up the sample and injected half of it into mice. The mice lived. He then mixed the other half with a living, non pathogenic bacteria strain and injected the mixture into mice. The mice died. These results best support which of the following conclusions.
a substance had been transferred from pathogenic to nonpathogenic bacteria,
Frederick Griffith heat-killed a culture of pathogenic bacteria. He split the sample and injected half of it into mice. The mice lived. He then mixed the other half of the sample with a living, nonpathogenic bacteria strain and injected the mixture into mice. The mice died. Which of the following describes a treatment that would help clarify interpretation of these data?
examining tissue from the dead mice (injected with mixed sample) for the presence of pathogenic bacteria.
which of the following characteristics allowed Hershey and Chase to determine whether the genetic material was made of DNA or protein?
DNA contains phosphoro0us, whereas protein does not.
which of the following investigators was responsible for determining that DNA contains equal amounts of adenine and thymine, and equal amounts of guanine and cytosine.
erwin chargaff
which of the following combinations of base pairs will be found in a molecule of DNA.
A + C = G + T
Two students decided to repeat the Hershey and Chase experiment, with modifications. Like Hershey and Chase they used radioactive sulfur but they substituted radioactive nitrogen for radioactive phosphate. They reasoned that each nucleotide has only one phosphate and two to five nitrogen atoms. Thus, labeling the nitrogen atoms would provide a stronger signal than labeling the phosphates. Which of the following is the biggest shortcoming in their experimental design?
The radioactivity would not distinguish between DNA and proteins because proteins contain nitrogen.
which of the following statements accurately describes difference between DNA replication in prokaryotes and DNA replication in eukaryotes.
prokaryotic chromosomes have a single origin of replication, whereas eukaryotic chromosomes have many.
