Microbiology Unit 2

Which of the following statements is correct about splicing?

Splicing can occur in eukaryotes and viruses

Which of the following structures is recognized by the required for the binding of a small ribosomal subunit to bacterial mRNA?

Shine-Dalgarno sequence

A hypothetical nucleic acid was analyzed and found to contain 25% A, 20% G, 15% C, 40% T. What is this molecule?

Single stranded DNA

What is DNA denaturation?

Separation of two strands due to hydrogen bond breakdown

If a DNA molecule is found to be composed of 40% thymine, the percentage of guanine would be?

10%

Which of the following is not a product of glycolysis?

2 molecules of CO2

What is the name of the inhibition process when inhibitor binds to the active site of the enzyme?

Competitive

What is the RNA sequence that the sequence TGCACGT will be transcribed into?

ACGUGCA

What is the final electron acceptor in the alcoholic fermentation?

Acetaldehyde

Which of the following molecules enters Kreb's cycle after the transition step?

Acetyl-CoA

Which of the following are purines?

Adenine and Guanine

Which of these metabolic pathways produces highest number of ATP molecules per one molecule of glucose?

Aerobic respiration

Which of the following terms best describes the arrangement of the strands of the dsDNA molecule?

Antiparallel helical double strand

Which of the following statements about the regulation of enzymatic activity is correct?

Apoenzyme requires a cofactor to form the functional holoenzyme

Where does translation begin?

At the start codon

Which of the following statements is true about the extrachromosomal DNA in living cells?

Bacterial extrachromosomal DNA can be found in plasmids

Which of the following statements is correct regarding the gene transduction in bacteria?

Bacteriophage carries a piece of host DNA from one bacteria to another

Which disease is associated with Epstein-Barr virus infection?

Burkett's lymphoma

In the molecule of dsDNA, the ratio of quantities for which bases equals 1?

C/G

What happens during the Calvin Benson cycle?

Carbohydrates are synthesized from CO2

What is the best description for the reaction of hydrolysis?

Catabolic exergonic

Most bacteria, fungi, protozoa, use organic chemicals as the source for both energy and carbon. How do we call them?

Chemoheterotrophs

Which of the following statements correctly compares DNA and RNA?

DNA is more stable than RNA

Which enzyme adds complimentary bases to the growing chain during DNA replication?

DNA polymerase III

An error in which process may lead to the spontaneous mutation in the DNA?

DNA replication

Where does the energy for ATP directly come from?

Diffusion of hydrogen ions through the ATP synthase

What is the correct description of the the translation process?

During translation, one codon of mRNA is translated into one amino acid

Which of these statements regarding enzymes is false?

Enzyme increases both the state of the reaction and the ratio of the products

When does fermentation occur?

In the absence of oxygen

Which of the following is true about the chromosomes and chromosomal DNA in living cells?

Eukaryotic DNA is bound to histones

When staphylococcus aureus is present in the patient's blood, its coagulase enzyme may cause clot formation. Based on the information provided, what is this enzyme, most likely?

Exoenzyme

Which of the following combinations represent reduced forms of compounds?

FADH2 and NADH

Which enzyme breaks hydrogen bonds and unzips dsDNA molecule?

Helicase

Which of the following statements is true about B-oxifation as a metabolic pathway?

In B-oxidation, fatty acids are oxidized, producing acetyl-CoA

What is the mechanism of mutation caused by the ionizing radiation?

Introduction of double strand breaks

Lactose regulates the production of enzymes from the inducible lactose operon this way:

It binds to the repressor protein and releases it from the DNA

Enzyme's optimal pH is 7. Which of the following statements is correct regarding this enzyme?

It can work at pH 6 with lower efficiency than at pH 7.

Which of the following statements is false about cytomegalovirus?

It causes sever disease in immunocompetent individuals

What is the role of the DNA polymerase I in the excision repair?

It fills the gap in the DNA molecule after the removal of the mutated fragment

What is the role for primer in the DNA replication?

It is necessary for DNA polymerase III to start DNA synthesis

What happens to oxygen in the water molecule during photosynthesis?

It is oxidized forming molecular oxygen

Which of the following statements is true about the conjugation?

It requires sex pilus

Which strand of newly synthesized DNA molecule grows in the continuous way along with the replication fork?

Leading strand

What is the difference between ribonucleotides and deoxyribonucleatides?

Ribonucleotides have ribose instead of deoxyribose and ribonucleotides have uracil instead of thymine

CAU encodes aminoacid histidine. CAA encodes amino acid glutamine. If CAU is changed to CAA, how should we call this mutation?

Missense

What happens during non-competitive inhibition?

Molecule of inhibitor bings to the allosteric site of an enzyme

Which of the following molecules serve as electron carriers in the bacterial cell?

NADH and FADH2

In which cells does herpes simplex virus normally establish latency?

Neurons

Which of these molecules/ions can be a final electron acceptor in the anaerobic respiration?

Nitrate

What does repressor bind to?

Operator

DNA molecule is directional. What does that mean?

Phosphate residue connects 5' and 3' carbons of the adjacent sugar residues

What is the sequence that is recognized by the RNA polymerase during transcription initiation?

Promoter

Which of these statements about the typical sizes of microbial genomes is true>

Protozoan genomes are larger than bacterial genomes

What is the complication of Streptococcus pyrogens infection that affects the heart and joints leading to arthritis and endocarditis?

Rheumatic fever

Which of the following microorganisms is the common cause of community-acquired meningitis in adults?

Streptococcus pneumoniae

Which of the following statements is false about herpesvirus

They incorporate their genome in the cellular chromosomes

Which of the following statements about riboswitches is correct?

They are regulatory elements in the DNA and RNA molecule

What is the function of the terminal repeats in the process of transcription?

They are the signal for transcription termination

What is the major function of the minor and major grooves on the DNA molecules?

They are the sites for protein binding

Which of the following is true about inducible operons?

They are usually regulated by the substrate of enzymes they encode

Which of the following statements is false regarding herpesvirus

They are zootonic

In Kreb's cycle, molecule of citric acid (C6) is oxidized to oxaloacetic acid (C4). Where do the two carbons go?

They become two molecules of CO2

Which of the following descriptions of chemoautotrophs is correct?

They derive energy from the chemicals and carbon from inorganic sources

How do intercalating agents cause mutations?

They get between the nitrogenous bases distorting the DNA molecule

What is the function of the proteins of the electron transport chain (ETC)

To oxidize NADH and FADH2 and to pump H+ across the membrane

What is the function of miRNA in the cell?

To regulate that stability of mRNA transcripts

What is the role for the topoisomerase IV

To separate concatenated chromosomes

Which of the following sequences of events is correct for the gene expression in eukaryotes

Transcription - splicing - translation

Which of the following statements is correct regarding the gene expression in eukaryotes vs prokaryotes?

Transcription and translation in prokaryotes happen almost simultaneously.

What is the name of the process when bacterial cell obtains the free DNA plasmid from the environment?

Transformation

What is the result of DNA replication?

Two DNA molecules, each with one new strand and one original strand.

Which of the following herpesvirus infection is vaccine preventable?

Varicella zoster virus

Prescence of which biological macromolecules is, generally speaking, abnormal in the cytoplasm of a eukaryotic cell>

dsDNA and ssDNa

Which of the following molecules conveys the genetic information from the nucleus to the cytoplasm of a eukaryotic cell?

mRNA