CHAPTER 12

Front

What is the TATA box?

Back

A core promoter element recognized by transcription factors that is crucial for the initiation of transcription in eukaryotic cells.

Front

What is the consequence of a mutated polyadenylation signal sequence in a gene?

Back

The mRNA will be degraded prematurely, leading to a loss of functional mRNA.

Front

Which enzyme adds the poly-A tail to eukaryotic mRNA?

Back

Polyadenylate polymerase.

Front

What percentage of cellular RNA is typically ribosomal RNA (rRNA)?

Back

Approximately 80%.

Front

What is Rho-independent termination in prokaryotic transcription?

Back

A termination signal that causes RNA polymerase to dissociate from the DNA without the help of proteins.

Front

What is the role of transcription factors in gene expression?

Back

Transcription factors bind to specific DNA sequences to regulate the transcription of genes.

Front

What is the function of the 5' cap on eukaryotic mRNA?

Back

The 5' cap protects mRNA from degradation and assists in ribosome binding during translation.

Front

What is the difference between exons and introns?

Back

Exons are coding sequences that remain in mRNA after splicing, while introns are non-coding sequences that are removed.

Front

What is the significance of the poly-A tail in mRNA?

Back

The poly-A tail enhances the stability of mRNA and aids in its export from the nucleus.

Front

What is the function of RNA polymerase?

Back

RNA polymerase synthesizes RNA from a DNA template during transcription.