How are Proteins Made? - Transcription and Translation

• What is the process of making proteins called?

  Protein synthesis
• What are the two main steps of protein synthesis?


  • Transcription
  • Translation
• What happens during transcription?


  A single gene of DNA is copied into a structure called mRNA
• What is the role of mRNA in protein synthesis?


  It carries the genetic information from DNA to the ribosome
• Where is the genetic material of a cell contained?

  In the nucleus
• Why is DNA essential to life?


  It contains thousands of genes that code for proteins
• What are genes?


  Small sections of DNA that code for specific sequences of amino acids
• What is the function of ribosomes in protein synthesis?


  They read mRNA and assemble amino acids into proteins
• Why can't DNA leave the nucleus?


  Because it is too large to exit the nucleus
• What does mRNA stand for?


  Messenger RNA
• How does the structure of mRNA differ from DNA?


  mRNA is shorter, single-stranded, and contains uracil instead of thymine
• What is the process of transcription?


  1. RNA polymerase binds to DNA before the gene starts
  2. DNA strands separate to expose bases
  3. RNA polymerase reads DNA bases and synthesizes mRNA
  4. mRNA bases are complementary to DNA bases
  5. RNA polymerase detaches after synthesizing mRNA
• What is the template strand in transcription?


  The DNA strand used to make mRNA
• What is a codon?


  A group of three bases on mRNA that codes for a specific amino acid
• How many different amino acids do cells use to make proteins?


  20 different amino acids
• What is the role of tRNA in translation?


  It brings amino acids to the ribosome based on the mRNA codons
• How does tRNA ensure the correct amino acid is brought to the ribosome?


  Each tRNA has an anticodon that is complementary to the mRNA codon
• What are the steps of translation?


  1. mRNA and ribosome bind together
  2. tRNA brings the correct amino acid to the ribosome
  3. Ribosome joins amino acids together
  4. Ribosome moves along mRNA, allowing new tRNA to bind
  5. Process repeats until a complete protein is formed
• What happens to the amino acid chain after it detaches from the ribosome?


  It folds up to form a protein
• What is the significance of the ribosome in protein synthesis?


  It is the site where amino acids are assembled into proteins