features of the genetic code

• What are the three key features of the genetic code?

  Degenerate, universal, and non-overlapping
• What is a start codon?

  Three bases at the start of a gene
• What does the start codon code for?

  Amino acid methionine
• What are the three bases of the start codon on DNA?

  TAC
• What is the function of a stop codon?

  It signals the end of translation
• How many stop codons are there?

  Three
• What happens when the ribosome reaches a stop codon?

  The ribosome detaches and translation stops
• What does it mean that the genetic code is degenerate?

  Most amino acids are coded by multiple triplets
• How many different amino acids does the genetic code need to code for?

  20
• What is the mathematical formula to prove the genetic code's combinations?

  Four to the power of n
• If one base coded for amino acids, how many combinations would there be?

  Four
• If two bases coded for amino acids, how many combinations would there be?

  Sixteen
• If three bases coded for amino acids, how many combinations would there be?

  Sixty-four
• Why is the genetic code considered degenerate?

  It allows multiple triplets for one amino acid
• What is a silent mutation?

  A mutation that does not change the protein
• What does it mean that the genetic code is universal?

  Same triplet codes for the same amino acid
• How does the universality of the genetic code help in gene technologies?

  It allows gene transfer between species
• What does non-overlapping mean in the genetic code?

  Each base is part of only one triplet
• What is the advantage of a non-overlapping genetic code?

  Minimizes impact of mutations on proteins
• What are introns?

  Sections of DNA that don't code for amino acids
• What percentage of DNA is made up of introns?

  Over 90 percent
• What are exons?

  Sequences of bases that code for amino acids
• What is the definition of a genome?

  Complete set of DNA within one cell
• What is the definition of a proteome?

  Full range of proteins in one cell
• How does the genome change compared to the proteome?

  The genome does not change; the proteome does
• Why do specialized cells produce different proteins?

  They respond by producing needed proteins
• How many DNA base pairs do humans have in their genome?

  About three billion
• How many DNA base pairs do bacteria have in their genome?

  About six hundred thousand
• What are the three features of the genetic code?

  • Degenerate: Multiple triplets for one amino acid
  • Universal: Same triplet codes across species
  • Non-overlapping: Each base is part of one triplet
• What is the difference between introns and exons?

  • Introns: Non-coding sections of DNA
  • Exons: Coding sequences of DNA
• What is the difference between genome and proteome?

  • Genome: Complete set of DNA in a cell
  • Proteome: Full range of proteins in a cell