Transcription and Translation Flashcards
gene
a sequence of DNA that codes for a specific polypeptide or RNA molecule
translation
the second step of gene expression during which a polypeptide chain is produced from an mRNA molecule
mutation
a change in the nucleotide sequence of a segment of DNA that codes for a gene product
gene expression
the process by which gene products are synthesized by a cell
reading frame
the correct grouping of codons in mRNA that produces the intended polypeptide sequence; determined by the start codon and can be shifted by the addition or deletion of nucleotides in DNA
ribosomes
cellular structures that bind to mRNA and provide the location for the assembly of the corresponding polypeptide chain
mutagen
a physical or chemical agent such as X rays, ultraviolet radiation, and carcinogens (e.g.:benzene), that causes mutations in DNA
genetic code
specific sequences of nucleotide bases in mRNA, arranged in codons that correspond to each of the 20 different amino acids
messenger RNA (mRNA)
a type of RNA that carries genetic information from the nucleus to the cytosol
base-pair substitution
the replacing of one base pair with another in DNA
template strand
one of the two strands of DNA that provides the instructions for building a polypeptide chain; also called the anti-sense strand or non-coding strand
messenger RNA (mRNA)
a type of RNA that carries genetic information from the nucleus to the cytosol
ribosomal RNA (rRNA)
a type of RNA found in ribosomes that catalyzes the formation of peptide bonds between amino acids during the process of translation
point mutation
a change in just one nucleotide in the coding strand of DNA
coding strand
the sequence of DNA analogous to the mRNA produced from the template strand; also called the sense strand
transfer RNA (tRNA)
a type of RNA that carries amino acids to the ribosome during the process of translation
missense mutation
a mutation in DNA that results in the replacement of one amino acid by another