Protein Synthesis

• What is the one-way flow of information in living things called?

  Central Dogma
• What are the two main steps in protein synthesis?


  Transcription and Translation
• What is the Central Dogma of molecular biology?


  • DNA → RNA → Protein
• Where does transcription occur in eukaryotes and prokaryotes?


  In the nucleus of eukaryotes and the cytoplasm of prokaryotes
• What enzyme is responsible for transcription?


  RNA polymerase
• What does RNA polymerase do during transcription?


  It binds to DNA at promoter regions and separates the strands
• What type of RNA is produced during transcription?

  mRNA
• What base pairing occurs during transcription?


  A pairs with U and G pairs with C
• If the DNA strand is TACGCATGGAAT, what is the corresponding mRNA sequence?


  AUG-CGU-ACC-UUA
• What is the start codon in the genetic code?


  AUG
• What amino acid does the start codon AUG code for?


  Methionine
• How many stop codons are there in the genetic code?


  Three
• What are the three stop codons?


  UGA, UAA, UAG
• What is the role of tRNA in translation?


  • Brings amino acids to the ribosome
  • Matches its anticodon with the mRNA codon
  • Helps in forming the polypeptide chain
• Where does mRNA go after it is formed?


  It comes out of the nucleus and attaches to a ribosome
• What happens to the polypeptide chain during translation?


  It grows until it reaches a stop codon
• What is the function of the anticodon in tRNA?


  It is complementary to the mRNA codon
• How does the process of transcription differ from translation?


  Transcription copies DNA into RNA, while translation converts RNA into proteins
• What are the steps involved in the process of translation?

  1. mRNA attaches to the ribosome
  2. tRNA brings amino acids to the ribosome
  3. Anticodon of tRNA pairs with codon of mRNA
  4. Polypeptide chain grows until a stop codon is reached
• How many possible codons are there in the genetic code?


  64
• What are the bonds that link amino acids together called?

  Peptide bonds
• What is the amino acid sequence coded for by the mRNA sequence AUG-CGU-ACC-UUA?


  Methionine-Arginine-Threonine-Leucine