Red Cross Lifeguarding
Genetics WSU MBIOS/BIOL 301, Exam 1,
Dr. Julie Stanton, Spring Fall Newest
Solution
Genetic material was first hypothesized to be what? Why? - ANS ✔✔ - Protein because DNA seemed to
be too simple to contain all of the necessary genetic information
What 3 key experiment lead to the discovery that DNA was genetic material? - ANS ✔✔ - Griffith
experiment, Avery, Hershey-Chase.
Describe the Griffith Experiment. - ANS ✔✔ - Griffith used two strands of Dipolococcus pnemoniae, IIIS
(virulent) and IIR(non-virulent). When a mouse was injected with heat-killed IIIS, the mouse lived. When
the mouse was injected with both, it died. Conclusion: Something in the heat-killed IIIS transformed the
IIR into virulent bacteria.
Describe the Avery Experiment. - ANS ✔✔ - The IIIS bacteria was heat-killed in a test tube after being
centrifuged. Then the carbohydrate, lipid, and protein medium was removed. Some of the heat-killed
IIIS bacteria were added to a solution containing IIR bacteria. This was repeated, but adding either
protease, RNase, or DNase. A transformation of the IIR cells occurred every time except when DNase
was added.
Describe the Hershey-Chase Experiment. - ANS ✔✔ - E. coli cells were infected with T2 phages. In
different flasks, they either had their DNA labeled with P32 or their proteins labeled with S35. The
solutions were individually blended to separate the phage from the bacteria and then centrifuged. The
P32 labeled DNA ended up in the bottom of the test tube where the cells were located and the S35
labeled protein ended up in the supernatant, where the T2 phage was located.
What is a radioisotope? How can it relate to the study of genetics? - ANS ✔✔ - A radioactive isotope of
an atom. It can be incorporated during synthesis of macromolecules and allows researchers to trace the
tagged macromolecules.
1
, Red Cross Lifeguarding
What are the monomers of nucleic acids? The polymers? - ANS ✔✔ - Monomers: Nucleotides.
Polymers: DNA or RNA.
What are the two types of nitrogenous bases? In which group is each nitrogenous base located? - ANS
✔✔ - Purine (Six-sided ring attached to five-sided ring): Guanine & Adenine.
Pyrimidine (Six-sided ring): Cytosine, Uracil, Thymine.
What is the difference in the sugar of DNA and RNA? - ANS ✔✔ - DNA: Deoxyribose with an H at 2' C.
RNA: Ribose with and OH at 2' C.
Describe the phosphate group. - ANS ✔✔ - P bound to 4 O.
Highly negatively charged.
What is a phosphodiester bond? - ANS ✔✔ - A bond between two nucleotides in which a phosphate
group connects two sugars.
What is Chargaff's Rule? - ANS ✔✔ - %A=%T
%C=%G
What did Rosalind Franklin contribute to the study of DNA's structure? - ANS ✔✔ - She used X-Ray
diffraction to view the structure of DNA, noting that is was helical, double-stranded, and had about 10
base pairs per turn.
What is on the outside/inside of DNA? Where do proteins often bind on DNA? - ANS ✔✔ - The
sugar/phosphate groups are on the outside and the bases are on the inside.
Proteins often bind to the major (22 Angstrom) and minor grooves (12 Angstrom) of DNA.
2
Genetics WSU MBIOS/BIOL 301, Exam 1,
Dr. Julie Stanton, Spring Fall Newest
Solution
Genetic material was first hypothesized to be what? Why? - ANS ✔✔ - Protein because DNA seemed to
be too simple to contain all of the necessary genetic information
What 3 key experiment lead to the discovery that DNA was genetic material? - ANS ✔✔ - Griffith
experiment, Avery, Hershey-Chase.
Describe the Griffith Experiment. - ANS ✔✔ - Griffith used two strands of Dipolococcus pnemoniae, IIIS
(virulent) and IIR(non-virulent). When a mouse was injected with heat-killed IIIS, the mouse lived. When
the mouse was injected with both, it died. Conclusion: Something in the heat-killed IIIS transformed the
IIR into virulent bacteria.
Describe the Avery Experiment. - ANS ✔✔ - The IIIS bacteria was heat-killed in a test tube after being
centrifuged. Then the carbohydrate, lipid, and protein medium was removed. Some of the heat-killed
IIIS bacteria were added to a solution containing IIR bacteria. This was repeated, but adding either
protease, RNase, or DNase. A transformation of the IIR cells occurred every time except when DNase
was added.
Describe the Hershey-Chase Experiment. - ANS ✔✔ - E. coli cells were infected with T2 phages. In
different flasks, they either had their DNA labeled with P32 or their proteins labeled with S35. The
solutions were individually blended to separate the phage from the bacteria and then centrifuged. The
P32 labeled DNA ended up in the bottom of the test tube where the cells were located and the S35
labeled protein ended up in the supernatant, where the T2 phage was located.
What is a radioisotope? How can it relate to the study of genetics? - ANS ✔✔ - A radioactive isotope of
an atom. It can be incorporated during synthesis of macromolecules and allows researchers to trace the
tagged macromolecules.
1
, Red Cross Lifeguarding
What are the monomers of nucleic acids? The polymers? - ANS ✔✔ - Monomers: Nucleotides.
Polymers: DNA or RNA.
What are the two types of nitrogenous bases? In which group is each nitrogenous base located? - ANS
✔✔ - Purine (Six-sided ring attached to five-sided ring): Guanine & Adenine.
Pyrimidine (Six-sided ring): Cytosine, Uracil, Thymine.
What is the difference in the sugar of DNA and RNA? - ANS ✔✔ - DNA: Deoxyribose with an H at 2' C.
RNA: Ribose with and OH at 2' C.
Describe the phosphate group. - ANS ✔✔ - P bound to 4 O.
Highly negatively charged.
What is a phosphodiester bond? - ANS ✔✔ - A bond between two nucleotides in which a phosphate
group connects two sugars.
What is Chargaff's Rule? - ANS ✔✔ - %A=%T
%C=%G
What did Rosalind Franklin contribute to the study of DNA's structure? - ANS ✔✔ - She used X-Ray
diffraction to view the structure of DNA, noting that is was helical, double-stranded, and had about 10
base pairs per turn.
What is on the outside/inside of DNA? Where do proteins often bind on DNA? - ANS ✔✔ - The
sugar/phosphate groups are on the outside and the bases are on the inside.
Proteins often bind to the major (22 Angstrom) and minor grooves (12 Angstrom) of DNA.
2
