Advanced Higher Biology: The proteome

What is the central dogma of molecular biology?

• DNA directly translates into proteins without the need for RNA.

• RNA is translated into DNA, which is then transcribed into proteins.

• Proteins are converted into RNA and then transcribed into DNA.

• DNA is transcribed into RNA, which is then translated into proteins.

Approximately what percentage of DNA is expressed as protein?

• 10%

• 4%

• 50%

• 25%

What is the role of tRNA?

• It is a type of non-coding RNA that does not play a role in protein synthesis.

• It is involved in gene expression and protein synthesis.

• It helps in the replication of DNA.

• It acts as a regulatory sequence in DNA.

What is alternative splicing?

• A method of DNA replication.

• The process of converting DNA directly into proteins.

• The addition of a poly-A tail to mRNA.

• A process that removes introns from RNA transcripts.

What are post-translational modifications?

• The transcription of mRNA from DNA.

• The replication of proteins.

• Changes to a protein's structure after it has been synthesized.

• The removal of exons from RNA.

What can increase the diversity of the proteome beyond the genome?

• Alternative splicing and post-translational modifications.

• Increased number of genes.

• Decreased RNA stability.

• Uniform gene expression.

What is the proteome?

• The entire set of proteins expressed by a genome at any given time.

• The total set of DNA in an organism.

• A single type of protein produced in a cell.

• The complete set of RNA transcripts in a cell.

Why is the proteome larger than the genome?

• Due to alternative splicing and post-translational modifications.

• Because the genome shrinks over time.

• Due to the increase in RNA types.

• Because of the large number of genes.

What factors can influence the set of proteins expressed by a cell?

• Disease, signaling molecules, cellular stress, and metabolic activity.

• The temperature of the environment only.

• The size of the cell only.

• The age of the cell only.

What is the significance of proteolytic cleavage in protein processing?

• It transcribes RNA into DNA.

• It adds phosphate groups to proteins.

• It replicates proteins for cell division.

• It cuts proteins into smaller units, potentially activating them.