Bio302 Exam One – Flashcards

Proteins bind selectively to small-molecule targets called ligands. The selection of one ligand out of a mixture of possible ligands depends on a number of weak, noncovalent interactions in the protein's ligand-binding site. Where is the binding site typically located in the protein structure?

Although all protein structures are unique, there are common structural building blocks that are referred to as regular secondary structures. Some have alpha helices, some have beta sheets, and still others have a combination of both. What makes it possible for proteins to contain these common structural elements?

Sometimes, chemical damage to DNA can occur just before DNA replication begins, not giving the repair system enough time to correct the error before the DNA is duplicated. This gives rise to mutation. If the adenosine in the sequence TCAT is depurinated and not repaired, which of the following is the point mutation you would observe after this segment has undergone two rounds of DNA replication?

The N-terminal tail of histone H3 can be extensively modified, and depending on the number, location, and combination of these modifications, these changes may promote the formation of heterochromatin. What is the result of heterochromatin formation?

Besides the distortion in the DNA backbone caused by a mismatched base pair, what additional mark may also be found on eukaryotic DNA to indicate which strand needs to be repaired?

Although the chromatin structure of interphase and mitotic chromosomes is very compact, DNA-binding proteins and protein complexes must be able to gain access to the DNA molecule. Chromatin-remodeling complexes provide this access by ?

Which of the following statements is false in regards to transcription? A: A new RNA molecule can begin to be synthesized from a gene before the previous RNA molecule's synthesis is completed. B: If two genes are to be expressed in a cell, these two genes can be transcribed with different efficiencies. C: RNA polymerase is responsible for both unwinding the DNA helix and catalyzing the formation of the phosphodiester bonds between nucleotides. D: None of the above

Which of the following statements is true? A: Ribosomes have large complex of 4 RNAs and more than 80 proteins B: Ribosomes have binding sites from mRNA and 3 binding sites for tRNA C: rRNA contains the catalytic activity that joins amino acids together D: Ribosomes bind multiple tRNAs at a time E: All of the above

Transcription in bacteria differs from transcription in a eukaryotic cell because ______?

Using the table below, translate the following eukaryotic messenger RNA sequence

What is the one letter abbreviation of the amino acid tryptophan?

Match the general type of biochemical reaction catalyzed in the left column with the class of enzyme listed in the column on the right. A. Removes a phosphate group from a molecule B. Adds phosphate groups to molecules C. Joins two ends of DNA together Catalyzes the synthesis of polymers such as RNA and DNA Nuclease, Polymerase, Ligase, Phosphatase, Kinase

The core histones are proteins that have a globular domain at the C-terminus and a long, extended "tail" at the N-terminus. Which of the following is/are true of the N-terminal "tail" of these histones? A: It is subject to covalent modifications B: It helps DNA pack tightly C: It binds to DNA by electrostatic interactions D: All of the above

Which of the following statement about a newly synthesized strand of DNA is true? A: It was synthesized from a single origin solely by continuous DNA synthesis B: It was synthesized from a single origin by a mixture of continuous and discontinuous DNA synthesis C: It was synthesized from multiple origins solely by discontinuous DNA synthesis D: It was synthesized from multiple origins by a mixture of continuous and discontinuous DNA synthesis

A nucleosome contains two molecules each of histones ____ as well as histones H3 and H4.

A nucleosome core particle contains a core of histone with DNA wrapped around it approximately ____.

Nucleosomes are aided in their formation by the high proportion of

Which amino acid will be on the tRNA that is the first to bind to the P-site of the ribosome?

Which of the following does not occur before an eukaryotic mRNA is exported from the nucleus?

Which of the following statements about RNA splicing is false? A: Conventional introns are not found in bacterial genes B: For a gene to function properly, every exon must be removed from the primary transcript in the same fashion on every mRNA molecule produced from the same gene C: Small RNA molecules in the nucleus perform the splicing reactions D: Splicing usually occurs after the 5? cap has been added to the 5' end of the primary transcript.

What is the three letter abbreviation for the amino acid Glutamine?

Transcription is similar to DNA replication in that ___________?

Unlike DNA, which typically forms a helical structure, different molecules of RNA can fold into a variety of 3D shapes. This is largely because ___________?

You have a segment of mRNA that contains the following sequence 5'-AUAGGCAUUCGAUCCGGAUAGCAU-3' Which of the following DNA molecules would be the coding strand from which this segment of mRNA was arranged? Using the transcript information from above, which of the following DNA molecules would be the template strand from which this segment of mRNA was produced? 5'-ATAGGCATTCGATCCGGATAGCAT-3'

DNA replication is considered semiconservative because ____.

Telomeres serve as caps at the end of linear chromosomes. Which of the following is false regarding the replication of telomere sequences during lagging strands synthesis?

True or false: Alternative splicing is a process that allows many different proteins to be produced from the same gene.

If the cytosine in the sequence TCAT is deaminated and not repaired, which of the following is the point mutation you would observe after this segment has undergone two round of DNA replication?

Homologous recombination is an important mechanism in which organisms use a homologous copy of the DNA as a template to fix double-strand breaks without loss of genetic information. Which of the following is not necessary for homologous recombination to occur?

The correct folding of proteins is necessary to maintain healthy cells and tissues. Unfolded proteins are responsible for such neurodegenerative disorders as Alzheimer's, Huntington's, and Creutzfeld-Jacob disease (the specific faulty protein is different for each disease). What is the ultimate fate of these disease-causing, unfolded proteins?

Because all DNA polymerases synthesize DNA in a specific direction, and the parent strands are antiparallel, DNA replication is accomplished with the use of two diff mechanisms: continuous and discontinuous. A=continuous, B=discontinuous, C=both. 30. Primase 31. Single-strand binding protein 32. Sliding clamp 33. RNA primers 34. DNA helicase