Protein Synthesis and the Epigenome

What is the molecular weight of the 30s ribosomal subunit?

1.4 mil Daltons

How many RNA molecules are found in the 50s ribosomal subunit?

3

How many proteins are found in the 30s ribosomal subunit?

33

How many proteins are in the 50s ribosomal subunit?

50

The growing polypeptide chain is released from the ribosomes when: A) a chain terminating codon is reached B) a chain terminating tRNA binds to the ribosome C) the 7-methyl guanosine cap is reached D) the poly A tail is reached

A) a chain terminating codon is reached

Which site of the tRNA molecule binds to the mRNA molecule? A) anticodon B) codon C) amino acid D) 5 prime end

A) anticodon

Separation of molecules according to size can be achieved by which of the following? A) gel filtration chromatography B) ion-exchange chromatography C) affinity chromatography D) isoelectric chromatography E) X-ray diffraction

A) gel filtration chromatography

Amino acids are joined together into a protein chain by which of the following? A) transfer RNA B) DNA polymerase C) hydrogen bonds D) messenger RNA

A) transfer RNA

List the 3 binding sites for tRNA on the 50s ribosomal subunit (in order of binding)

A, P, E

Identify the mRNA sequence that would be made from the following DNA template: TACAAAGGCTTA

AUGUUUCCGAAU

What type of epigenetic tag loosens DNA and allows for transcription?

Acetyl groups

Protein synthesis rates in prokaryotes are limited by the rate of mRNA synthesis. If RNA synthesis occurs at the rate of 50 nucleotides/sec, then the rate of protein synthesis occurs at: A) 10 amino acids/sec B) 17 amino acids/sec C) 25 amino acids/sec D) 50 amino acids/sec

B) 17 amino acids/sec

The DNA code for an amino acid consists of a sequence of: A) 4 nitrogen containing bases taken from 3 possible bases B) 3 nitrogen bases taken from 4 possible bases C) 3 nitrogen bases taken from 5 possible bases D) 5 nitrogen bases taken from 4 possible bases

B) 3 nitrogen bases taken from 4 possible bases

For what type of product does an intron code? A) a complex of tRNA molecules B) no functional product C) an RNA D) mRNA E) a poly-A tail

B) no functional product

Genes act by directing the synthesis of: A) carbohydrates B) proteins C) lipids D) sugars E) all of these

B) proteins

The addition of the -amanitin, a known inhibitor of DNA-dependent mRNA synthesis, to growing cells will most likely cause protein synthesis to: A) stop immediately B) stop as mRNA becomes depleted C) stop as thymidine becomes depleted D) stop as the ribosomes become inactivated E) be unaffected

B) stop as mRNA becomes depleted

Which of the following RNAs bind to an amino acid? A) mRNA B) tRNA C) rRNA D) hnRNA

B) tRNA

The ribosomes are composed of: A) proteins B) RNA C) a and b D) lipids

C) a and b

Which of the following is not a necessary component of translation? A) anticodon B) mRNA C) ligase D) amino acid

C) ligase

The amino acid sequence of proteins is determined by: A) secondary structures B) nitrogen content C) nucleic acids D) peptide bonds

C) nucleic acids

In a cell, the transfer of genetic information from DNA to RNA occurs in the: A) cell membrane B) ribosome C) nucleus D) chloroplast E) none of these

C) nucleus

The site for production of most proteins within a cell is the: A) centrioles B) nuclei C) ribosome D) vacuoles E) nome of these

C) ribosome

The molecules which carry amino acids to the ribosomes are: A) protein molecules B) mRNA molecules C) tRNA molecules D) DNA molecules

C) tRNA molecules

If a mutation occurs in a segment of a DNA molecule, it is reasonable to conclude that: A) enzyme synthesis is not affected B) protein synthesis is unchanged C) the complementary RNA would also be altered D) the mutation is harmful to the organism

C) the complementary RNA would also be altered

Which of the following amino acids starts all proteins synthesis? A) glycine B) proline C) thymine D) methionine

C) thymine

What is the function of the 50s ribosomal subunit?

Catalyses peptide bond formation

What is the function of Dicer?

Chops up double-stranded RNA

What is the function of Cas9?

Cuts the DNA

Methyl groups bond to which pyrimidine?

Cytosine

Proteins contain ___ different amino acids, whereas DNA and RNA are composed of ___ different nucleotides. A) 20, 64 B) 3, 20 C) 4, 20 D) 20, 4

D) 20, 4

Which of the following is not necessary for protein synthesis to occur, once transcription is completed? A) tRNA B) mRNA C) Ribosomes D) DNA

D) DNA

Which is required for protein synthesis? A) tRNA B) mRNA C) rRNA D) all of these

D) all of these

The anticodon of tRNA: A) binds to rRNA B) binds to an amino acid C) binds to the Shine Dalgarno sequence D) binds to an mRNA codon

D) binds to an mRNA codon

How many bases of nucleic acid determine a single amino acid? A) four B) one C) two D) three

D) three

RNAi requires what type of RNA? Single stranded or double stranded

Double stranded

Exons of a gene are defined as: A) the untranslated regions of the corresponding mRNA B) regions in the corresponding mRNA that are involved in initiation of transcription C) regions that are not transcribed by RNA polymerase D) regions that are exercised from the corresponding protein after it is synthesized E) regions that remain in the corresponding mRNA after splicing

E) regions that remain in the corresponding mRNA after splicing

Coding regions of DNA are termed?

Exons

Who won the nobel prize for RNA interference?

Fire and Mello

What is CRISPR?

Gene-editing tool

Acetyl groups bind to what chromosomal structure?

Histones

Noncoding regions of DNA are termed?

Introns

What scientist broke the genetic code and determined the codons for each amino acid?

Marshall Nuremberg

What type of epigenetic tag tightens DNA and prevents transcription?

Methyl groups

What organelle is the site of transcription?

Nucleus

RNA interference is involved in what type of control?

Post transcriptional

What enzyme is involved in transcription?

RNA polymerase

Where does translation take place?

Ribosome

What is the function of the 30s ribosomal subunit?

Spell-checker, makes sure strands are correct

A codon is a sequence of mRNA that has gone through which process?

Splicing