Protein Structure and Genetic Code

These flashcards cover key vocabulary terms and their definitions related to protein structure, genetic expression, and mutations, derived from the lecture notes.

Amino Acid

The monomer of proteins; there are 20 different amino acids with unique side chains.

Polypeptide

A polymer formed from the linkage of amino acids via peptide bonds.

Peptide Bond

A covalent bond that links amino acids together in proteins.

Codon

A triplet of bases in mRNA that codes for a specific amino acid.

Start Codon

AUG, which signifies the beginning of translation.

Stop Codons

UGA, UAA, UAG; these codons signal the end of translation.

Universal Genetic Code

The genetic code is used by nearly all organisms, demonstrating evolutionary relationships.

Redundant Genetic Code

Refers to the fact that some amino acids are encoded by more than one codon.

Unambiguous Genetic Code

No codon corresponds to more than one amino acid.

tRNA

Transfer RNA; carries amino acids to the ribosome during protein synthesis.

mRNA

Messenger RNA; conveys genetic information from DNA to the ribosome.

rRNA

Ribosomal RNA; a structural component of ribosomes.

Aminoacyl-tRNA Synthetase

An enzyme that attaches the appropriate amino acid to its corresponding tRNA.

Ribosome

A cellular structure made of rRNA and proteins that facilitates the translation of mRNA into proteins.

Mutation

An alteration in the DNA sequence of an organism that can affect protein functionality.

Point Mutation

A mutation where a single nucleotide change alters a single amino acid.

Frameshift Mutation

A mutation caused by insertions or deletions that shift the reading frame of the genetic code.

Somatic Cells

All body cells except germ cells; mutations here are not inherited.

Germ Cells

Cells that produce sperm and eggs; mutations can be inherited.

Genetic Modification

A biotechnological method to alter the genetic makeup of organisms, often to produce desired proteins.

Post-translational Modification

Chemical changes to proteins after synthesis that may alter their function.

Proteasome

A protein complex that breaks down damaged or unneeded proteins.