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