In his transformation experiments, what phenomenon did Griffith observe?

• Mixing a heat-killed pathogenic strain of bacteria with a living nonpathogenic strain can convert some of the living cells into the pathogenic form.

• Mixing a heat-killed nonpathogenic strain of bacteria with a living pathogenic strain makes the pathogenic strain nonpathogenic

• Infecting mice with nonpathogenic strains of bacteria makes them resistant to pathogenic strains.

• Mice infected with a pathogenic strain of bacteria can spread the infection to other mice.

Which of the following statements describes the process of transformation in bacteria?

• A strand of DNA is created from an RNA molecule.

• A strand of RNA is created from a DNA molecule.

• Bacterial cells are infected by a phage DNA molecule.

• External DNA is taken into a cell, becoming part of the cell's genome.

A heat-killed, phosphorescent (light-emitting) strain of bacteria is mixed with a living, non-phosphorescent strain. Further observations of the mixture show that some of the living cells are now phosphorescent. Which of the following observations would provide the best evidence that the ability to phosphoresce is a heritable trait?

• evidence that DNA was passed from the heat-killed strain to the living strain

• evidence that protein passed from the heat-killed strain to the living strain

• especially bright phosphorescence in the living strain

• phosphorescence in descendants of the living cells

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

Which of the following facts did Hershey and Chase make use of in trying to determine whether DNA or protein is the genetic material?

• DNA contains sulfur, whereas protein does not.

• DNA contains phosphorus, whereas protein does not.

• DNA contains nitrogen, whereas protein does not.

• DNA contains purines, whereas protein includes pyrimidines.

Which of the following investigators was (were) responsible for the discovery that in DNA from any species, the amount of adenine equals the amount of thymine, and the amount of guanine equals the amount of cytosine?

• Alfred Hershey and Martha Chase

• Oswald Avery, Maclyn McCarty, and Colin MacLeod

• Erwin Chargaff

• Matthew Meselson and Franklin Stahl

Cytosine makes up 42% of the nucleotides in a sample of DNA from an organism. Approximately what percentage of the nucleotides in this sample will be thymine?

• 8%

• 16%

• 42%

• 58%

Hershey and Chase set out to determine what molecule served as the unit of inheritance. They completed a series of experiments in which E. coli was infected by a T2 virus. Which molecular component of the T2 virus actually ended up inside the cell?

• protein

• RNA

• ribosome

• DNA

In the polymerization of DNA, a phosphodiester bond is formed between a phosphate group of the nucleotide being added and which of the following atoms or molecules of the last nucleotide in the polymer?

• the 5' phosphate

• C6

• the 3' OH

• a nitrogen from the nitrogen-containing base

Which of the following statements accurately describes the differences between DNA replication in prokaryotes and DNA replication in eukaryotes?

• Prokaryotic chromosomes have histones, whereas eukaryotic chromosomes do not.

• Prokaryotic chromosomes have a single origin of replication, whereas eukaryotic chromosomes have many

• The rate of elongation during DNA replication is slower in prokaryotes than in eukaryotes.

• Prokaryotes produce Okazaki fragments during DNA replication, but eukaryotes do not.

What is meant by the description "antiparallel" regarding the two strands that make up the DNA double helix?

• The double helix structure of DNA creates nonparallel strands

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

• Base pairings create unequal spacing between the two DNA strands

• One strand contains only purines and the other contains only pyrimidines.