Biology chapter 12/15.1-

DNA vs RNA

DNA stores genetic information; RNA plays various roles in protein synthesis and gene regulation.

Deoxyribose

The sugar found in DNA.

Ribose

The sugar found in RNA.

Promoter

A regulatory sequence that initiates transcription.

Transcription

The process of copying DNA sequence into mRNA.

Translation

The process of assembling amino acids into a polypeptide based on the mRNA template.

Structural gene

Contains the coding sequence for a protein.

Termination of transcription

Occurs when RNA polymerase reaches a terminator sequence, releasing the mRNA.

Codon

A sequence of three nucleotides in mRNA that correspond to specific amino acids.

Anticodon

A complementary sequence of three nucleotides in tRNA that pairs with the codon in mRNA.

Frameshift mutation

Mutation caused by addition or deletion of nucleotides that alters the reading frame.

Nonsense mutation

A mutation that changes an amino acid to a stop codon.

Missense mutation

A mutation that changes one amino acid to another.

Silent mutation

A mutation that does not change the amino acid sequence.

Induced mutations

Mutations that result from exposure to mutagens.

Spontaneous mutations

Mutations that occur naturally without external influence.

Carcinogen

A substance that promotes cancer, not all carcinogens are mutagens.

Somatic mutations

Mutations that occur in non-reproductive cells and are not passed to offspring.

Germ line mutations

Mutations that occur in reproductive cells and can be inherited.

Chemical mutagens

Cause DNA changes through chemical interactions.

Physical mutagens

Cause mutations through physical means, such as radiation.

Proofreading

The process by which DNA polymerases correct errors during replication.

DNA Repair

Mechanisms that fix damaged DNA to prevent mutations.

Detoxification

Process where enzymes metabolize harmful substances to minimize mutagenic effects.