The Triple Threat Test AP Biology (Chapters 13,14,15)😅💀

What are the three parts that make up DNA?

The three parts are a phosphate group, a sugar (deoxyribose), and a nitrogenous base.

What is the role of DNA Polymerase during DNA replication?

DNA Polymerase is an enzyme that copies DNA by adding nucleotide bases to the 3' end of a new DNA strand.

What holds the nitrogenous base pairs together in the DNA structure?

A→T pairs share two hydrogen bonds, while G→C pairs share three hydrogen bonds.

What is a leading strand in DNA replication?

The leading strand is the DNA strand where primer is added and bases are added continuously from the 3’ end towards the 5’ end.

What is the significance of the TATAAA box in transcription?

The TATAAA box is a sequence of bases that provides a landing site for RNA Polymerase to start transcription.

What is the process of changing pre-mRNA into mRNA called?

RNA Processing.

What are introns and exons in the context of pre-mRNA?

Introns are the non-coding sequences of pre-mRNA, while exons are the coding sequences that remain in mRNA after processing.

What is the start codon for protein synthesis?

AUG, which codes for methionine.

What happens during the elongation phase of transcription?

RNA Polymerase continues to add RNA nucleotides to the growing RNA strand.

What occurs during the termination phase of transcription?

Transcription stops and the RNA molecule is formed and released.

What is an operon?

An operon is a cluster of genes controlled by a single promoter.

What is the function of a repressor protein in gene regulation?

A repressor protein binds to the operator and stops the transcription of the gene.

What distinguishes a repressible operon from an inducible operon?

Repressible operons are normally ON and can be turned OFF, while inducible operons are normally OFF and can be turned ON.

What is a frameshift mutation?

A mutation that removes or changes amino acids in a protein, potentially making it nonfunctional.

What is a nonsense mutation?

A change to a codon that converts it into a stop codon, potentially resulting in a nonfunctional protein.

How does a silent mutation affect an organism?

A silent mutation changes a nucleotide but does not change the amino acid it codes for, which typically has little to no effect.