Molecular Biology Concepts Quiz

Paternally imprinted gene = Not expressed from the chromosome provided from the mother, but expressed from a chromosome from the father snRNAs = Functional RNAs that can repress translation of certain mRNAs Poly-A polymerase = Processing factor that adds the poly-A sequence to the 3'-end of prokaryotic mRNAs Histone methylation = Epigenetic mark that can be found in chromatin of expressed or repressed genes

True (A)

<p>To repress translation of certain mRNAs</p> Signup and view all the answers

<p>sigma</p> Signup and view all the answers

<p>GAL7 (D)</p> Signup and view all the answers

<p>Paternally imprinted gene (D)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>poly-A</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>GAL4 is a modular protein because it has distinct functional domains that can operate independently to regulate gene expression.</p> Signup and view all the answers

<p>UAS</p> Signup and view all the answers

<p>Wild type = Expressed GAL4- = Not expressed GAL80- = Expressed GAL3- = Not expressed</p> Signup and view all the answers

<p>The GC-rich box and the CCAAT box (A), An upstream enhancer (B), The TATA box (D)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>A regulatory mechanism that allows premature termination of transcription in response to specific signals.</p> Signup and view all the answers

<p>transcriptional elongation</p> Signup and view all the answers

<p>Both B and C (B)</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>The TATA box and additional transcription factors</p> Signup and view all the answers

<p>RNA polymerase II = Transcriptional elongation AraC = Regulation of the arabinose operon Rho factor = Transcriptional termination in E. coli AAUAAA sequence = Transcriptional termination in eukaryotes</p> Signup and view all the answers

<p>Transfer RNA (D)</p> Signup and view all the answers

<p>True (A)</p> Signup and view all the answers

<p>To facilitate the splicing of pre-mRNA.</p> Signup and view all the answers

<p>mRNA</p> Signup and view all the answers

<p>RNA contains ribose sugars. (C)</p> Signup and view all the answers

<p>Messenger RNA = Carries genetic information from DNA to ribosomes Transfer RNA = Brings amino acids to ribosomes Ribosomal RNA = Makes up the structure of ribosomes Small nuclear RNA = Involved in RNA splicing</p> Signup and view all the answers

<p>False (B)</p> Signup and view all the answers

<p>RNA polymerase holoenzyme</p> Signup and view all the answers

<p>UAC</p> Signup and view all the answers

<p>Mutation in the repressor gene (A), Mutation in the promoter region (B)</p> Signup and view all the answers

<p>True (A)</p> Signup and view all the answers

<p>repressor</p> Signup and view all the answers

<p>5'-GUA-3', 5'-GUC-3', 5'-GUG-3'</p> Signup and view all the answers

<p>Mutant 3 (A)</p> Signup and view all the answers

<p>Mutant 1 = Constitutive high expression Mutant 2 = No expression Mutant 3 = Low expression in presence of lactose</p> Signup and view all the answers

<p>rNTPs and RNA polymerase (D)</p> Signup and view all the answers

<p>4/9 (B)</p> Signup and view all the answers

<p>True (A)</p> Signup and view all the answers

<p>Side chain</p> Signup and view all the answers

<p>peptide</p> Signup and view all the answers

<p>Methionine = Contains a sulfur atom in its side chain Valine = Branched side chain with two methyl groups Alanine = Simple side chain consisting of a single methyl group Leucine = Branched side chain with an extra carbon</p> Signup and view all the answers

<p>To transport amino acids to the ribosome</p> Signup and view all the answers

<p>True (A)</p> Signup and view all the answers

A gene that is expressed only if it comes from the father's chromosome.

Functional RNAs involved in splicing.

Enzyme that adds a poly-A tail to the mRNA.

An epigenetic mark affecting gene expression.

Small RNAs that can regulate mRNA translation.

Dosage compensation mechanism in mammals using one X chromosome.

Conserved nucleotide in introns needed for splicing.

A protein needed for transcription initiation.

The two strands of DNA run in opposite directions, one 5' to 3' and the other 3' to 5'. This allows for complementary base pairing between the two strands.

RNA contains ribose sugars and uracil, while DNA contains deoxyribose sugars and thymine.

A multi-subunit protein complex that initiates transcription by binding to a promoter sequence on DNA.

A modified guanine nucleotide added to the 5' end of eukaryotic mRNAs, protecting the mRNA from degradation.

RNAs are always synthesized 5' to 3' direction, regardless of which DNA strand is used as a template.

A sequence of adenine nucleotides added to the 3' end of eukaryotic mRNAs, increasing stability and aiding in translation.

A large complex of proteins and RNA molecules that removes introns from pre-mRNA during eukaryotic RNA processing.

GAL4 is a protein that acts as a transcriptional activator for the GAL7 and GAL10 genes. It binds to upstream activating sequences (UAS) located before these genes.

The presence of galactose activates the GAL4 protein, leading to the transcription of the GAL1, 2, 7 and 10 genes.

GAL80 is a repressor protein that inhibits GAL4's activity by physically binding to it. This prevents GAL4 from activating the GAL genes in the absence of galactose.

GAL3 is an enzyme that converts galactose into galactose-1-phosphate, which is the signal that activates GAL4 and releases it from inhibition by GAL80.

A modular protein is a protein that is composed of discrete functional units, or domains, that can be combined in different ways to create different proteins with different functions.

The process of creating RNA molecules outside of a living cell, typically in a laboratory setting. This method involves using enzymes like RNA polymerase and providing the necessary building blocks (rNTPs).

Ribonucleoside triphosphates are the building blocks of RNA. Each rNTP consists of a ribose sugar, a nitrogenous base (adenine, guanine, cytosine, or uracil), and three phosphate groups.

The enzyme responsible for synthesizing RNA molecules. It uses a DNA template to create a complementary RNA strand.

A sequence of three nucleotides in mRNA that codes for a specific amino acid.

A sequence of three nucleotides in DNA or RNA.

The fraction of all possible three-nucleotide combinations (triplets) that code for the amino acid proline.

A functional group consisting of a nitrogen atom bonded to two hydrogen atoms (-NH2).

A functional group consisting of a carbon atom double-bonded to an oxygen atom and single-bonded to a hydroxyl group (-COOH).

RNA is always synthesized from the 5' to 3' direction, regardless of which DNA strand it's transcribed from.

These sequences are located upstream of the transcription start site in prokaryotes and are recognized by the RNA polymerase holoenzyme.

AraC protein acts as an activator in the presence of arabinose, allowing transcription of genes needed for arabinose metabolism. In the absence of arabinose, it acts as a repressor, preventing transcription.

This mechanism regulates gene expression by allowing translation and transcription to occur simultaneously in prokaryotes.

Phosphorylation of the CTD of RNA polymerase II is essential for the elongation phase of transcription in eukaryotes.

Termination of transcription in E. coli depends on either a rho factor binding to specific sequences or formation of a stable hairpin structure in the mRNA.

Transcriptional termination in human cells is primarily dependent on the presence of an AAUAAA sequence in the mRNA 3'-UTR, followed by polyadenylation.

RNA polymerase II is the primary enzyme involved in transcribing protein-coding genes in eukaryotes.

The sequence of nucleotides on a tRNA that base pairs with the AUG start codon on mRNA. It is 3'-UAC-5'.

The rules that govern non-standard base pairing between the third position of a codon and the first position of an anticodon. This allows some tRNAs to recognize multiple codons.

There are two tRNAs that can recognize Valine codons. They have anti-codons 3'-CAU-5' and 3'-CAG-5'.

This tRNA can recognize the codons GUU, GUC, and GUA. This is due to the wobble rules, which allow the third position of the codon to pair with more than one nucleotide in the first position of the anticodon.

This tRNA can recognize the codons GUG and GUA.

Constitutive expression of lacZ, Y, and A genes, meaning they are expressed all the time regardless of the presence or absence of lactose.

A mutation in the lac repressor gene (lacI) that prevents the repressor from binding to the operator, thus allowing constitutive expression of the lac operon genes.

No expression of lacZ, Y, and A genes in either the presence or absence of lactose.