Bio 1: Genetic Code, Translation, and Mutations

Vocabulary practice flashcards covering molecular genetics concepts from CK-12 Reading Notes #22, #23, and codon breaking activities, including transcription, translation, codon characteristics, and mutation types.

Genetic Code

The set of rules used to "read" the instructions in DNA.

Codon

A group of 3 nitrogen bases in RNA and DNA that serves as the genetic code word for a single amino acid or for a start or stop signal.

Start Codon

The codon that begins translation and establishes the reading frame of mRNA.

Reading Frame

The triplet grouping of ribonucleotides established by the start codon according to which mRNA is read codon by codon until reaching a stop codon.

Universal (Genetic Code Characteristic)

The property of the genetic code establishing that all known living organisms use the exact same genetic code.

Unambiguous (Genetic Code Characteristic)

The property of the genetic code meaning each individual codon codes for just one specific amino acid.

Redundant (Genetic Code Characteristic)

The property of the genetic code wherein most amino acids are encoded by more than one codon.

Translation

The process where the genetic code in mRNA is read, one codon at a time, to make a protein.

Ribosome

A molecular structure consisting of rRNA and proteins that is responsible for translation by reading the sequence of codons in mRNA after it leaves the nucleus.

tRNA

Molecules that bring amino acids to the ribosome in the correct sequence to ensure translation occurs properly.

Transcription

The process by which a sequence of messenger RNA codons is synthesized from a DNA sequence in triplets.

Mutation

A change in the DNA or RNA sequence.

Germline Mutations

Mutations that occur in gametes; they are especially significant because they can be transmitted to offspring and be present in every cell of the offspring.

Somatic Mutations

Mutations that occur in other body cells; they are confined to just one cell and its daughter cells, have little effect on the organism, and cannot be passed on to offspring.

Point Mutation

A mutation that alters the genetic code by changing the codon code, which is less serious than a chromosomal alteration and may sometimes be silent.

Chromosomal Alteration

A major structural mutation that can be very dangerous and cause significant harm to an organism.

Silent Mutation

A type of point mutation where the mutated codon codes for the exact same amino acid as the original codon.

Missense Mutation

A type of point mutation where the mutated codon codes for a different amino acid.

Nonsense Mutation

A type of point mutation where the mutated codon becomes a premature stop codon.

Frameshift Mutations

Mutations caused by insertions or deletions of base letters that dramatically shift the reading frame of codons in mRNA, altering the resulting protein product.