BMB Unit 2

Splicing occurs after the 5′ cap has been added to the end of the primary transcript

true

The genetic code is redundant

true

The sugar in RNA is ribose, while in DNA it is deoxyribose

true

The three steps of each cycle of PCR are Denaturation, Annealing, and Amplification

true

cDNA libraries are made from RNA transcripts

true

convential introns are not found in bacterial genes

true

in splicing, introns are excised but exons are retained

true

miRNA is transcribed in the nucleus and exported to the cytoplasm

true

rRNA contains the catlytic activity that joins amino acids together

true

restriction endonucleases produce either sticky ends(which can join with other strands) or blunt ends(which cannot)

true

restriction enzymes recognize and cute DNA at specific sites only

true

splicing occurs after the 5' cap has been added to the 5' end of the primary transcript

true

Prominent part of many regulatory proteins contains which of the following DNA binding domains

zinc finger domain

Ribosomes large subunit

catalyzes the formation of the peptide bonds that link the amino acids together into a polypeptide chains

DNA ligase

A linking enzyme essential for DNA replication; catalyzes the covalent bonding of the 3' end of a new DNA fragment to the 5' end of a growing chain.

what expresses differences in the human genome?

2-6 nucleotide repetitions

An incoming aminoacyl-tRNA carrying the next amino acid in the chain will bind to which site by forming base pairs with the exposed codon in the mRNA

A

Which of the following molecules of RNA would you predict to be the most likely to fold into a specificstructure as a result of intramolecular base-pairing?A 5′-CCCUAAAAAAAAAAAAAAAAUUUUUUUUUUUUUUUUAGGG-3′ B 5′-UGUGUGUGUGUGUGUGUGUGUGUGUGUGUGUGUGUGUGUG-3′ C 5′-AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA-3′ D 5′-GGAAAAGGAGAUGGGCAAGGGGAAAAGGAGAUGGGCAAGG-3′

A 5′-CCCUAAAAAAAAAAAAAAAAUUUUUUUUUUUUUUUUAGGG-3′

Sanger sequence

A procedure in which chemical termination of daughter strands help in determining the DNA sequence.

Codon

A specific sequence of three adjacent bases on a strand of DNA or RNA that provides genetic code information for a particular amino acid

Polymerase Chain Reaction (PCR)

A technique for amplifying DNA in vitro by incubating with special primers, DNA polymerase molecules, and nucleotides.

Does tRNA link with its amino acid before or afterbinding to its codon in RNA?

After

Which statement is true regarding the steps for mRNA being translated into protein in eukaryotes? A The mRNA is transported to the cytosol after 5'-capping and polyadenylation, but RNA splicingo ccurs in the cytosol. B the mRNA is translated in the nucleus and then the fully translated protein is then transported to the cytosol. C the mRNA is transported to the cytosol after 5'-capping, polyadenylation and RNA splicing. D The mRNA is transcribed in the cytosol and therefore, ribosomes can translate the message into protein immediately after transcription.

C the mRNA is transported to the cytosol after 5'-capping, polyadenylation and RNA splicing.

The number of rRNA molecules that make up a ribosome greatly exceeds the number of protein molecules found in the ribosome

False

Unlike DNA, RNA uses a uracil base and a deoxyribose sugar.

False

the DHU (D) loop named after dihydrouridine (D) is an un-modified nucleotide

False

Genes in eukaryotic cells often have intronic sequences coded for within the DNA. These sequences are ultimately not translated into proteins. Why?

Intronic sequences are removed from RNA molecules by the spliceosome, which works in the nucleus.

RNA in cells differs from DNA in that

It is single-stranded and can fold into a variety of structures

Transcription is similar to DNA replication in that

Nucleotide polymerization occurs only in the 5'-to-3' direction

Unlike DNA, which typically forms a helical structure, different molecules of RNA can fold into a varietyof three-dimensional shapes. This is largely because

RNA is single-stranded

What is one application of PCR?

Testing for and positivly identifying HIV through T-Cells in the blood

The Central Dogma is

The principle that genetic information flows from DNA to RNA to protein.

Ribosomes are found in the cytosol as well as in the ER.

True

The four main wobble base pairs are guanine-uracil (G-U), hypoxanthine-uracil (I-U), hypoxanthine-adenine (I-A), and hypoxanthine-cytosine (I-C)

True

The small subunit of the ribosome is important for binding to the mRNA

True

Are GAU and GAA a wobble pair?

Yes

Which of these is correct about Eukaryotic mature mRNA transcript after it emerges from the RNA polymerase: it contains 5' N^7-methylguanosine cap contains poly (A) tail does not contain introns

all of the above

wobble pairing

allows tRNA to read triple codons as the same amino acid

restriction endonucleases

an enzyme that cuts DNA at specific sites, producing small fragments used in genetic engineering.

Histone

any of a group of basic proteins found in chromatin.

Small Interfering RNAs (siRNA)

bind to and degrade foreign RNA, the Handle the infections

Micro RNAs (miRNA)

can bond with other mRNAs, are single-stranded, derived from introns

You have a segment of DNA that contains the following sequence: 5′-GGACTAGACAATAGGGACCTAGAGATTCCGAAA-3′ 3′-CCTGATCTGTTATCCCTGGATCTCTAAGGCTTT-5′ You know that the RNA transcribed from this segment contains the following sequence: 5′-GGACUAGACAAUAGGGACCUAGAGAUUCCGAAA-3′ Is the transcribed RNA sequence shown correctly or incorrectly?

correctly

RNA is largely single-stranded, this means

different molecules of RNA fold into a variety of 3-D shapes

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.

false

In splicing exons are excised but introns are retained

false

Unlike DNA, RNA uses uracil base and deoxyribose sugar

false

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

false

histone modifications aren't inherited by daughter cells

false

ribosomes must bind to the 5' cap before initiating translationf

false

The sigma subunit of bacterial RNA polymerase

recognizes promoter sites in the DNA

Regulatory proteins determine whether gene expression is to be increased or decreased, they exerttheir control of gene expression at

gene transcriptional level

Anticodon

group of three bases on a tRNA molecule that are complementary to an mRNA codon

Why do genes in eukaryotic cells often have intronic sequences that are not ultimately translated into proteins

intronic sequences are removed by the RNA molecules by the spliceosome, which works in the nucleus

RNA in cells differs from DNA in that

it is single-stranded and can fold up into a variety of structures

Ribosomes small subunit:

matchs tRNA to the codons of the mRNA

Transcription is similar to DNA replication in that

nucleotide polymerization occurs only in the 5' to 3' direction

The nucleolus is the site of

rRNA synthesis and ribosome assembly

The two things that are absolutely essential for PCR (polymerase chain reaction) to occur are the DNA polymerase and

the DNA primer

Which of the following choices best describes how transcription occurs? 5′-GGACTAGACAATAGGGACCTAGAGATTCCGAAA-3′ 3′-CCTGATCTGTTATCCCTGGATCTCTAAGGCTTT-5'

the bottom strand is the template strand; RNA polymerase moves along this strand from3′ to 5'

5' UTR and 3' UTR which are non-protein coding sequences are retained

true

A cDNA library "ChIP" may contain all the genes expressed in a cell

true

A new RNA molecule can begin to be synthesized from a gene before the previous RNAmolecule's synthesis is completed

true

Both siRNA and miRNA are processed by Dicer and bind to proteins to form an RNA-induced silencing complex (RISC)

true

Cell type specific regulatory proteins ensure cell type (lineage) specific gene expression whereas simultaneously ensure that genes belonging to different lineages remain repressed. Is the statement true or false?

true

Conventional introns are not found in bacterial genes

true

DNA libraries are made from genome segments

true

DNA that is being transcribed by RNA is organized in a 3'-to-5' direction

true

DNA typically forms helical structures

true

If two genes are to be expressed in a cell, these two genes can be transcribed with differentefficiencies

true

In eukaryotic organisms the regulatory DNA sequences may be spread out over 1000s of base pairs.Usually, more than one regulatory factor binds to their respective regulatory DNA sequences of a gene and exerts a combinatorial control on the gene expression.

true

Methylation causes cytosine → 5-methylcytosine (suppression of gene expression)

true

RNA polymerase is responsible for both unwinding the DNA helix and catalyzing theformation of the phosphodiester bonds between nucleotides

true

Restriction enzymes recognize and cut DNA at specific sites only. Is this statement true or false?

true

Small RNA molecules in the nucleus perform the splicing reactions necessary for the removal of introns

true

Small RNA molecules in the nucleus perform the splicing reactions necessary for the removalof introns

true

with respect to regulatory proteins and general transcription factors, The general transcription factors that assemble at the promoter are the same for all genes transcribed by RNA polymerase

true

with respect to regulatory proteins and general transcription factors, the transcription regulators along with mediators recruit chromatin modifying proteins, areassembled at the promoter

true

with respect to regulatory proteins and general transcription factors, the transcription regulators and the locations of their DNA binding sites relative to the promotersare different for different genes

true