bio topic 24
10. Oswald Avery and his collaborators showed that the 'transforming principle' of Griffith was a. bacterial DNA. b. mouse DNA. c. polysaccharides. d. bacterial enzymes. e. lipids.
A
11. The works of Griffith and Avery showed that a. DNA is the genetic material. b. DNA is the genetic material of bacteria. c. DNA is the genetic eukaryotes. d. DNA is the genetic DNA viruses. e. the genetic material is contained in the nucleus of eukaryotic cells.
A
15. The radioactive material injected into the bacteria by the bacteriophages of Hershey-Chase indicated that a. DNA, not protein is the genetic material. b. protein is not an important part of the virus. c. DNA is not an important part of the virus. d. the bacterial cells had more need for P than for S. e. only P is needed to make new virus particles.
A
18. The bacteriophages used in Alfred Hershey's and Martha Chase's experiments showed that: a. DNA was injected into bacteria. b. DNA and protein were injected into bacteria. c. DNA remained on the outer coat of bacteria. d. proteins were injected into bacteria. e. proteins were responsible for the production of new viruses within the bacteria.
A
2. Acetabularia are organism best described as a. unicellular, photo-litho- C-¬autotrophs. b. multicellular, photo-litho- C-autotrophs. c. unicellular, chemo- organo- C-heterotrophs. d. multicellular, chemo-organo- C-heterotrophs.
A
21. In the Hershey-Chase experiment with bacteriophages, a. harmless bacterial cells permanently transformed into virulent cells b. DNA was shown to be the transforming principle of earlier bacterial transformation experiments c. the replication of DNA was conclusively shown to be semiconservative d. viral DNA was shown to enter bacterial cells and cause production of new viruses within the bacteria e. viruses inject their proteins, not their DNA, into bacterial cells
B
7. In Griffith's experiments, harmless bacteria changed and caused disease when they were mixed with a. dead mice. b. dead, virulent bacteria. c. bacteria isolated from sick mice. d. DNA from mice that had died from the bacterial disease. e. DNA from other avirulent (harmless) bacteria.
B
19. When Griffith injected mice with a combination of live rough-strain and heat-killed smooth-strain pneumococci, he discovered that a. the mice were unharmed b. the dead mice contained living rough-strain bacteria c. the dead mice contained living smooth-strain bacteria d. DNA had been transferred from the smooth-strain bacteria to mice e. DNA had been transferred from rough-strain bacteria to the smooth-strain bacteria
C
5. Griffith's experiments were done with a. Acetabularia mediteranea. b. Tobacco mosaic virus. c. Streptococcus pneumoniae. d. frog embryos. e. human babies
C
17. The first experimenters to use Griffith's transformation assay to identify the genetic material were: a. Meselson and Stahl. b. Watson and Crick. c. Franklin and Wilkins. d. Avery, MacLeod, and McCarty. e. Hershey and Chase.
D
20. Which of the following inspired Avery and his colleagues to perform the experiments demonstrating that the transforming principle in bacteria is DNA? a.the fact that A is equal to T, and G is equal to C b. Watson and Crick's model of DNA structure c. Meselson and Stahl's studies on DNA replication in E.coli d. Griffith's experiments on smooth and rough strains of pneumococci e. Hershey and Chase's experiments on the reproduction of bacteriophages
D
6. The bacteria that Griffith worked with killed mice only if they had a. been isolated from diseased mice. b. heat-killed. c. a cell wall. d. a polysaccharide-rich capsule. e. a visible nucleus.
D
9. Predict which injection(s) of the Griffith's experiments will kill the injected mice. Injection with a. live, avirulent, non— encapsulated bacteria. b. heat—killed, virulent, encapsulated bacteria. c. heat-killed, avirulent, non-encapsulated bacteria. d. live, avirulent, non— encapsulated bacteria AND heat— killed, virulent, encapsulated bacteria. e. live, avirulent, non— encapsulated bacteria AND heat— killed, avirulent, non— encapsulated bacteria. f. live, virulent, encapsulated
D
3. Hammerling's experiments strongly suggested that a. DNA is the genetic material. b. DNA is the genetic material of bacteria. c. DNA is the genetic material of eukaryotes. d. DNA is the genetic material of DNA viruses. e. the genetic material is contained in the nucleus of eukaryotic cells.
E
8. When the avirulent bacteria changed to virulent organisms in Griffith's experiments, they were said to be a. killed. b. potentiated. c. reactivated. d. virulated. e. transformed.
E
13. What radioactive isotope would you select to label only the nucleic acid of a virus (explain why!)? a. carbon (14C). b. phosphorus (32P) c. nitrogen (15N). d. oxygen (180). e. sulfur (35S).
b
14. The radioactive material injected into the bacteria by the bacteriophages of Hershey—Chase was a. carbon (14C). b. phosphorus(32P). c. nitrogen (15N). d. oxygen (180). e. sulfur (35S).
b
16. In the experiments of Griffith, the conversion of nonlethal R-strain bacteria to lethal S-strain bacteria: a. was the result of genetic mutation. b. was an example of the genetic exchange known as transformation. c. supported the case for proteins as the genetic material. d. could not be reproduced by other researchers. e. was an example of conjugation.
b
1. The organism Hammerling worked with was a member of the a. viruses. b. plants. c. algae. d. fungi. e. bacteria.
c
12. What radioactive isotope would you select to label only the proteins of a virus (explain why!)? a. carbon (14C). b. phosphorus (32P). c. nitrogen (15 N). d. oxygen (180). e. sulfur (35S).
e
