Microbiology Module 10 MC/FITB

Biochemistry of the Genome

Frederick Griffith infected mice with a combination of dead R and live S bacterial strains. What was the outcome, and why did it occur?

The mice will die. Transformation of genetic material from R to S was required

Why was the alga Acetabularia a good model organism for Joachim Hämmerling to use to identify the location of genetic material?

It is a large, asymmetrical, single cell easy to see with the naked eye.

Which of the following best describes the results from Hershey and Chase’s experiment using bacterial viruses with 35S-labeled proteins or 32P-labeled DNA that are consistent with protein being the molecule responsible for hereditary?

1. After infection with the ³⁵S-labeled viruses and centrifugation, only the pellet would be radioactive.

2. After infection with the ³⁵S-labeled viruses and centrifugation, both the pellet and the supernatant would be radioactive.

3. After infection with the ³²P-labeled viruses and centrifugation, only the pellet would be radioactive.

4. After infection with the ³²P-labeled viruses and centrifugation, both the pellet and the supernatant would be radioactive.

After infection with the 35S-labeled viruses and centrifugation, only the pellet would be radioactive.

Which method did Morgan and colleagues use to show that hereditary information was carried on chromosomes?

A. statistical predictions of the outcomes of crosses using true-breeding parents

B. correlations between microscopic observations of chromosomal movement and the characteristics of offspring

C. transformation of nonpathogenic bacteria to pathogenic bacteria

D. mutations resulting in distinct defects in metabolic enzymatic pathways

Correlations between microscopic observations of chromosomal movement and the characteristics of offspring

According to Beadle and Tatum's "one gene–one enzyme" hypothesis, which enzyme would eliminate the transformation of hereditary material from pathogenic bacteria to nonpathogenic bacteria?

Deoxyribonucleases.

Which of the following is not found within DNA?

Amino acids

If 30% of the bases within a DNA molecule are adenine, what is the percentage of thymine?

30%

Which of the following statement about base pairing in DNA is incorrect?

Adenine binds to guanine.

If a DNA strand contains the sequence 5ʹ-ATTCCGGATCGA-3ʹ, what is the sequence of the complementary strand of DNA?

3ʹ-TAAGGCCTAGCT-5

During denaturation of DNA, what happens?

Hydrogen bonds between complementary bases break

Which type of RNA codes for a protein?

mRNA.

A nucleic acid is purified from a mixture. The molecules are relatively small, contain uracil, and most are covalently bound to an amino acid. What was purified?

tRNA.

Which type of RNA is known for its catalytic abilities?

rRNA.

Ribosomes are composed of rRNA and what other component?

Protein.

What may use RNA as its genome?

A virus.

What describes the structure of the typical eukaryotic genome?

Linear.

Which of the following is typically found as part of the prokaryotic genome?

Plasmids.

Serratia marcescens cells produce a red pigment at room temperature. The red color of the colonies is an example of which of the following?

Phenotype.

Which gene would not likely be encoded on a plasmid?

Gene encoding enzymes for glycolysis.

Histones are DNA binding proteins that are important for DNA packaging in which of the following?

Eukaryotes and archaea

Carries an amino acid to the ribosome.

tRNA

Is a major component of the ribosome.

rRNA

Is a copy of the information in a gene.

mRNA

The element ____________ is unique to nucleic acids compared with other macromolecules.

Phosphorus

In the late 1800s and early 1900s, the macromolecule thought to be responsible for heredity was ______________.

protein

The end of a nucleic acid strand with a free phosphate group is called the ________.

5′ end

Plasmids are typically transferred among members of a bacterial community by ________ gene transfer.

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