29 Questions
What can break the chemical bonds in DNA, leading to mutations?
Certain chemicals and various forms of ionizing radiation
How can the activity of a transcription factor be altered?
By allosteric or covalent modulation
Which process regulates the initiation of protein assembly on a ribosome?
Posttranslational processing of proteins
What are environmental factors that increase the rate of mutation known as?
Mutagens
What is any alteration in the nucleotide sequence that spells out a genetic message in DNA known as?
Mutation
How can specific genes be regulated in response to signals?
Via gene transcription into mRNA
What happens if a gene corresponding to a particular protein ceases to be transcribed into mRNA?
The protein will not be formed after mRNA molecules break down.
What posttranslational modification involves cleaving the amino acid methionine?
Glycosylation
How can different proteins be derived from the same mRNA?
Posttranslational cleavage occurs.
Which process results in the formation of smaller peptides from a polypeptide chain?
Hydrolysis
In what scenario would a polypeptide chain be split at different points in different cells?
Based on the specificity of hydrolyzing enzymes
How does posttranslational cleavage impact the final protein product?
It results in the formation of multiple proteins from one mRNA.
What is required for a gene to be transcribed?
RNA polymerase must bind to the promoter region
How are most genes transcription regulated?
By transcription factors
What is the function of transcription factors in gene transcription?
Form preinitiation complex at the promoter
How do transcription factors influence the initiation of transcription?
Slow down or speed up the initiation process
What may happen if a transcription factor binds far from a gene's promoter region?
It will form a loop to bring it into contact with the promoter region
What is the role of accessory proteins in gene transcription?
Remove blocking nucleosomes at the promoter region
What is the role of the signal sequence in protein synthesis?
It binds to a complex of proteins known as a signal recognition particle.
Where do proteins that are destined to be secreted end up during protein assembly?
Rough endoplasmic reticulum lumen
What happens to integral membrane proteins within the endoplasmic reticulum membrane?
Enzymes remove the signal sequence from them.
What is the function of a signal recognition particle in protein synthesis?
Binds to the signal sequence on the growing polypeptide chain.
What is the fate of the signal sequence in most proteins within the endoplasmic reticulum?
Cleaved by enzymes within the lumen.
What happens when proteins are fed through a protein complex in the endoplasmic reticulum membrane?
They are targeted for secretion.
What is the primary function of a signal sequence in a protein?
To facilitate the protein's secretion from the cell
Which component of the transcription initiation complex recognizes the promoter region of a gene?
Transcription factor
What is the term for the non-coding regions within a gene?
Introns
Which of the following is NOT a consequence of a mutation?
Protein stability
What is the role of the proteasome in cellular function?
To degrade damaged proteins
Test your knowledge on protein synthesis and posttranslational modifications. Explore concepts such as gene transcription, mRNA translation, and amino acid sequence alterations.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
