bio315 exam 3

can form a DNA duplex by pairing with itself at each position?

5′-AAGCGCTT-3′

Which eukaryotic RNA polymerase is responsible for the synthesis of most mRNAs?

RNA poly II

To mark proteins that will be degraded through the proteasome, what modification occurs to the protein?

Ubiquitination of lysine residues

the DNA from two different species can often be distinguished by a difference in

ratio of A + T to G + C

If you want to engineer a cytoplasmic protein to become a resident RER protein, which of the following amino acid sequences would you need to add?

signal sequence to N-terminus and KDEL sequence to C-term

In the fusion event between vesicle and target membranes, ______ found in the target membrane interact with ______ found on vesicles to pull the two lipid bilayers together.

tSNAREs vSNAREs

Which of the following statements concerning endocytosis and phagocytosis is incorrect?

Engulfment of particles by phagocytosis is driven by microtubule formation in the cell.

All of the following concerning protein translation are true except:

The Kozak sequence is used in bacteria to locate the correct initiation codon

All of the following concerning bacterial transcription are true except:

Transcriptional termination is always a rho-dependent process

Regulation of ferritin to help detoxify the presence of intracellular iron is an example of:

Translational-level control

which initiation factor is a GTP-binding protein required for attachment of the first aminoacyl-tRNA?

IF2 eIF2

Which of the following eukaryotic pre-initiation complex factors recognizes the promoter TATA box?

TFIID

Inner membrane mitochondrial proteins use this complex during transport from the cytosol

TOM complex TIM22 complex

function of smooth endoplasmic reticulum

- Steroid hormone synthesis - Detoxification of organic compounds - Sequestering calcium

associated with mRNA stability and degradation

- Deadenylase - Decapping enzyme - 5'-3' exonuclease - Exosome

true about human genome

- Gene duplication may arise from unequal crossing over events, and leads to the evolution of multigene families. - Trinucleotide repeat expansion diseases can occur in introns, coding exons, and untranslated regions (UTRs). - The human genome consists of around 20,000 genes. - The most common type of genetic variability in humans is from single nucleotide differences

true about genome structure and stability

- Genome complexity in terms of size can be determined from DNA renaturation. - Gene families are represented in the non-repeated fraction of eukaryotic DNA. - Retrotransposons have an RNA intermediate and require reverse transcriptase. - Movement of transposons require the enzyme transposase.

true of histone modification

- Methylation of amino acids is linked to a heterochromatin state. - Acetylation of amino acids is linked to a euchromatin state

RNR-RNR hybridization involves what

- Secondary structure formation in rRNAs and tRNAs - Recognition of Shine-Dalgarno sequence in bacterial mRNAs - Recognition of 5' and 3' hnRNA splicing sites by the spliceosome - Correct tRNA association with mRNA codons during translation

What is the order of events that occur for the routing of a protein with a nuclear localization signal into the nucleus?

1- importin a/b association w protein 2- interaction of protein complex with cytoplasmic filament of the nuclear pore 3- Movement of protein complex through the nuclear pore 4- Association of protein complex with Ran-GTP 5- Transport of importin to the cytosol via Ran-GTP

Amino acids are charged onto their respective t-RNAs through the activity of _______.

Aminoacyl-tRNA synthetases

What biological process involves surrounding internal organelles like mitochondria with a double membrane for subsequent degradation through the lysosome?

Autophagy

How are most eukaryotic transcription regulators able to affect transcription when their binding sites in enhancers are far from the promoter?

By looping out the intervening DNA between their binding site and the promoter

what moves materials from the ERGIC and Golgi "backward" towards the ER

COPI-coated

what moves materials from the ER "forward" to the ERGIC and Golgi complex

COPII-coated

An example of constitutive heterochromatin would be_______.

Centromeres Telomeres

Which G protein mediates the release of clathrin-coated vesicles from the plasma membrane during receptor-mediated endocytosis?

Dynamin

During eukaryotic pre-mRNA processing, which enzymes are involved in modification of the 3' end?

Endonuclease and polyA polymerase

Which region of the nucleolus is associated with the location of rDNA?

Fibrillar center

Consider two genes that are next to each other on a chromosome

Gene A and gene B can be transcribed at different rates, producing different amounts of RNA within the same cell.

Which histone modification directs the formation of the most common type of heterochromatin via recruitment of HP1 proteins?

H3 lysine 9 methylation

During the formation of heterochromatin from euchromatin, what is the order of events that generally occurs at the level of the histone?

Histone deacetylation; histone methylation; HP1 protein binds to histones

Which of the following statements concerning the lac operon is not true?

It is a type of repressible operon

DNA packaging from the lowest level of organization to the highest level is:

Nucleosome, 30-nm fiber, supercoiled loop, mitotic chromosome

Formation of clathrin-coated vesicles during receptor-mediated endocytosis is initiated by which of the following molecules?

PI(4,5)P2

Which of the following proteins do you not expect the RNA from the rough endoplasmic reticulum to encode?

Peripheral proteins on the cytoplasmic face of the lipid bilayer

These amino acids line the channel of the nuclear pore to provide a hydrophobic environment.

Phenylalanine; glycine

A defect in the lamin A/C gene leads to what disease?

Progeria

Which of the following statements about the protein quality control system in the ER is false?

Proteins that are misfolded are degraded in the ER lumen

In terms of DNA structure and composition, which of the following is not true?

Pyrimidines are G and T

During ribosome docking at the rough endoplasmic reticulum, which of the following act as G proteins to hydrolyze GTP before translation resumes?

SRP SRP receptor

What GTP-binding protein plays a regulatory role in the formation and disassembly of the COPII coat?

Sar1

Which of the following is not true concerning protein processing?

Secreted proteins (e.g. neurotransmitters) are synthesized on 'free' ribosomes.

Which of the following statements concerning DNA is true?

The melting temperature of DNA increases as its GC content increases

Which of the following is not true about the glycosylation of proteins in the ER?

The oligosaccharide 'tree' is made up entirely of glucose

Which of the following is not true concerning transcription factors?

Transcription factors generally act as monomers

Concerning pre-RNA processing, which of the following is not true?

mRNAs have 3' methyladenine caps and 5' polyG tails