Practice Questions_dr. Schlegel_may_aug2011 _pt.2

Reviewed by Editorial Team
The ProProfs editorial team is comprised of experienced subject matter experts. They've collectively created over 10,000 quizzes and lessons, serving over 100 million users. Our team includes in-house content moderators and subject matter experts, as well as a global network of rigorously trained contributors. All adhere to our comprehensive editorial guidelines, ensuring the delivery of high-quality content.
Learn about Our Editorial Process
| By Rosssweetie
R
Rosssweetie
Community Contributor
Quizzes Created: 13 | Total Attempts: 103,942
| Attempts: 167
Quiz Flashcard
SettingsSettings
Please wait...
  • 1/15 Questions

    RNA polymerase initiates transcription by recognizing specific nucleotide sequences called __________. .

    • Promoters
    • Triphosphate deoxyribonucleotides
    • P site
    • Replication fork /bubble
    • Leading strand
Please wait...
About This Quiz

This quiz, created by Dr. Schlegel for the period May-August 2011, assesses knowledge in microbiology and genetics, focusing on mechanisms like quorum sensing, SOS response, and mutations. It's designed to enhance understanding of how genetic processes influence microbial behavior.

Genetics Quizzes & Trivia

Quiz Preview

  • 2. 

    "Jumping genes" that can move from one location to another in an organism's genome are called __________.

    • Transposons

    • Gene

    • Competent

    • Missense

    • Anticodon

    Correct Answer
    A. Transposons
    Explanation
    Transposons are "jumping genes" that have the ability to move from one location to another within an organism's genome. They are also known as transposable elements and can cause genetic changes by inserting themselves into different positions in the DNA sequence. This mobility allows transposons to play a role in evolution and can have both positive and negative effects on an organism's phenotype.

    Rate this question:

  • 3. 

    The SOS response is a DNA repair mechanism that responds to extreme DNA damage

    • True

    • False

    Correct Answer
    A. True
    Explanation
    The SOS response is a DNA repair mechanism that is activated in response to extreme DNA damage. When the DNA is severely damaged, the SOS response is triggered to prevent further damage and promote DNA repair. This response involves the upregulation of various genes involved in DNA repair and replication, as well as the activation of error-prone DNA polymerases that can introduce mutations in order to bypass the damaged DNA. Overall, the SOS response is an important mechanism to ensure the survival of cells under conditions of extreme DNA damage.

    Rate this question:

  • 4. 

    In generalized transduction, viruses carry random DNA sequences from one cell to another

    • True

    • False

    Correct Answer
    A. True
    Explanation
    Generalized transduction is a type of horizontal gene transfer where viruses, called bacteriophages, carry random fragments of host DNA from one bacterial cell to another. This occurs when a bacteriophage mistakenly packages host DNA instead of its own DNA during the viral replication process. As a result, when the virus infects another bacterial cell, it transfers this random DNA sequence, which can then be incorporated into the recipient cell's genome. Therefore, the statement that in generalized transduction, viruses carry random DNA sequences from one cell to another is true.

    Rate this question:

  • 5. 

    The __________ is the DNA strand that is synthesized continuously during DNA replication.

    • Promoters

    • Triphosphate deoxyribonucleotides

    • P site

    • Replication fork /bubble

    • Leading strand

    Correct Answer
    A. Leading strand
    Explanation
    The leading strand is the DNA strand that is synthesized continuously during DNA replication. This is because the leading strand is oriented in the 3' to 5' direction, which allows DNA polymerase to add nucleotides in a continuous manner. In contrast, the lagging strand is oriented in the opposite direction (5' to 3') and requires the synthesis of short Okazaki fragments that are later joined together. Therefore, the leading strand is the correct answer as it is the strand that is synthesized continuously during DNA replication.

    Rate this question:

  • 6. 

    The point at which a DNA double helix is "unzipped" is the __________.

    • Promoters

    • Triphosphate deoxyribonucleotides

    • P site

    • Replication fork /bubble

    • Leading strand

    Correct Answer
    A. Replication fork /bubble
    Explanation
    The replication fork/bubble is the point at which a DNA double helix is "unzipped" during the process of DNA replication. This is where the two strands of the DNA molecule separate and serve as templates for the synthesis of new complementary strands. The replication fork/bubble is formed by the action of enzymes called helicases, which unwind the DNA helix and create a Y-shaped structure. The replication fork/bubble is a crucial site for DNA replication as it allows for the simultaneous synthesis of both leading and lagging strands.

    Rate this question:

  • 7. 

    A(n) __________ is a specific sequence of nucleotides that codes for a protein or an RNA molecule.

    • Transposons

    • Gene

    • Competent

    • Missense

    • Anticodon

    Correct Answer
    A. Gene
    Explanation
    A gene is a specific sequence of nucleotides that codes for a protein or an RNA molecule. It is the fundamental unit of heredity and carries the instructions for the synthesis of proteins, which are essential for the functioning and development of organisms. Genes are located on chromosomes and are responsible for the transmission of traits from parents to offspring. They play a crucial role in determining an individual's characteristics and are involved in various biological processes.

    Rate this question:

  • 8. 

    The __________ of a transfer RNA molecule is complementary to a codon in a messenger RNA molecule.

    • Transposons

    • Gene

    • Competent

    • Missense

    • Anticodon

    Correct Answer
    A. Anticodon
    Explanation
    The anticodon of a transfer RNA molecule is complementary to a codon in a messenger RNA molecule. The anticodon is a sequence of three nucleotides located on the tRNA molecule that specifically recognizes and binds to the corresponding codon on the mRNA during protein synthesis. This complementary base pairing between the anticodon and codon ensures that the correct amino acid is added to the growing polypeptide chain.

    Rate this question:

  • 9. 

    During translation, the growing polypeptide is positioned in the __________ of the ribosome

    • Promoters

    • Triphosphate deoxyribonucleotides

    • P site

    • Replication fork /bubble

    • Leading strand

    Correct Answer
    A. P site
    Explanation
    During translation, the growing polypeptide is positioned in the P site of the ribosome. The P site, also known as the peptidyl site, is one of the three binding sites on the ribosome where tRNA molecules are held during protein synthesis. The P site specifically holds the tRNA molecule carrying the growing polypeptide chain, allowing for the addition of new amino acids to the chain.

    Rate this question:

  • 10. 

    dATP and dCTP are examples of __________, the building blocks of DNA molecules

    • Promoters

    • Triphosphate deoxyribonucleotides

    • P site

    • Replication fork /bubble

    • Leading strand

    Correct Answer
    A. Triphosphate deoxyribonucleotides
    Explanation
    dATP and dCTP are examples of triphosphate deoxyribonucleotides, which are the building blocks of DNA molecules. These molecules are essential for DNA replication and synthesis, as they provide the necessary nucleotides to form the DNA chain. The "tri-" in triphosphate indicates that these molecules have three phosphate groups attached to the sugar backbone, providing energy for the DNA synthesis process. Deoxyribonucleotides refer to the type of sugar present in the molecule, which is deoxyribose. Therefore, dATP and dCTP are specific examples of triphosphate deoxyribonucleotides that contribute to the formation of DNA molecules.

    Rate this question:

  • 11. 

    Cells that are able to perform transformation are said to be __________.

    • Transposons

    • Gene

    • Competent

    • Missense

    • Anticodon

    Correct Answer
    A. Competent
    Explanation
    Cells that are able to perform transformation are referred to as "competent". This term is commonly used in molecular biology to describe cells that have been treated or engineered to take up foreign DNA molecules and incorporate them into their own genetic material. Competent cells have enhanced abilities to uptake and express exogenous DNA, making them useful tools in genetic engineering and biotechnology applications.

    Rate this question:

  • 12. 

    Binding of an autoinducer peptide to the sensor kinase of a quorum sensing system in a Gram-positive bacterium leads to altered regulation of genetic loci present on different parts of the chromosome and transcribed in different directions. Which of the following would best describe the organization of the genes targeted by this quorum-sensing system?

    • Divergent operons

    • Regulon

    • Contrary operons

    • Divergent regulation

    • Indirect regulation

    Correct Answer
    A. Regulon
    Explanation
    The organization of the genes targeted by this quorum-sensing system is best described as a regulon. A regulon refers to a set of genes or operons that are controlled by a common regulatory protein or mechanism. In this case, the binding of the autoinducer peptide to the sensor kinase leads to altered regulation of genetic loci present on different parts of the chromosome and transcribed in different directions. This suggests that the quorum-sensing system is coordinating the expression of multiple genes or operons, which is characteristic of a regulon.

    Rate this question:

  • 13. 

    The OmpR response regulator is activated in the presence of high solutes. One of the genes activated by OmpR is micF, whose nucleic acid product binds the ompF message and ends up reducing OmpF protein production, thereby reducing solute uptake. Which of the following terms would best describe micF and the stage at which it regulates OmpF production?

    • An antiterminator, acts on transcription

    • A kinase, regulates post-translationally

    • An antisense RNA, alters translation

    • An RNA stabilizing protein, alters translation

    • Sigma factor, acts on transcription

    Correct Answer
    A. An antisense RNA, alters translation
    Explanation
    The product of micF is a nucleic acid, so the most likely way it would bind to mRNA would be by sequence complementarity. The fact that it binds mRNA means that it is working AFTER transcription. Of the options presented, it would have to be an antisense RNA (also, all of the other options are proteins)

    Rate this question:

  • 14. 

    If the codon AUG, coding for methionine, were mutated to AAG, coding for lysine, this would be an example of a(n) __________ mutation.

    • Transposons

    • Gene

    • Competent

    • Missense

    • Anticodon

    Correct Answer
    A. Missense
    Explanation
    A missense mutation is a type of mutation where a single nucleotide change in the DNA sequence results in the substitution of one amino acid in the protein sequence for another. In this case, the codon AUG, which codes for methionine, is mutated to AAG, which codes for lysine. This change in the DNA sequence leads to the incorporation of lysine instead of methionine in the protein, resulting in a missense mutation.

    Rate this question:

  • 15. 

    Which 3 of the following could be required or produced by an organism using anaerobic respiration?

    • Organic acids

    • Cytochromes

    • Nitrite

    • Oxygen

    • Sulfate

    Correct Answer(s)
    A. Cytochromes
    A. Nitrite
    A. Sulfate
    Explanation
    Answer: B., C. and E. Organic acids are produced by fermentative pathways. Anaerobic respiration does not require oxygen as terminal electron acceptor—this function is taken by other molecules not derived from glycolysis (sulfate, nitrate, fumarate, ferric ion, etc). Anarobic respiration DOES require an ETC (hence cytochromes), an electron acceptor such as sulfate, and will produce a reduced form of that acceptor, such as nitrite.

    Rate this question:

Quiz Review Timeline (Updated): Mar 21, 2023 +

Our quizzes are rigorously reviewed, monitored and continuously updated by our expert board to maintain accuracy, relevance, and timeliness.

  • Current Version
  • Mar 21, 2023
    Quiz Edited by
    ProProfs Editorial Team
  • Jun 06, 2012
    Quiz Created by
    Rosssweetie
Back to Top Back to top
Advertisement
×

Wait!
Here's an interesting quiz for you.

We have other quizzes matching your interest.