the genetic code Flashcards
what is a gene?
a sequence of nucleotides that form part of a DNA molecule
what codes for the production of a specific polynucleotide?
the sequence of nucleotides
what else do genes control?
the protein structure - they determine the sequence in which the amino acids join together
what is a triplet?
a three-letter code
what does each triplet of bases in a gene code for?
one amino acid
how many different amino acids are there?
20
what is the start codon
methionine (TAC)
what do the start and stop codons do?
tells the cell where individual genes start and stop
what is the genetic code: (3)
- non-overlapping
- degenerate
- universal
why is the genetic code non-overlapping?
because each base is only read once in which codon its part of
why is the genetic code said to be degenerate?
as multiple codons can code for more than one amino acid
how many codons to amino acids are there?
64 codons and 20 amino acids
what is the benefit of a degenerate code?
it can limit the effect of mutations
why is the genetic code said to be universal?
as almost every organism uses the same code (there are few exceptions)
due to the universality of the genetic code, what process does this make possible?
genetic engineering (transfer of genetic material to species)
