Protein Synthesis

• What organelle is responsible for storing DNA?

  Nucleus
• What is the function of the nucleolus?


  It manufactures ribosomes
• What occurs during transcription?


  An mRNA copy of DNA is produced
• What happens to mRNA after it leaves the nucleus?


  It attaches to a ribosome
• What is produced during translation?


  A chain of amino acids known as a polypeptide
• What is the rough endoplasmic reticulum (RER) characterized by?


  Many ribosomes attached to its surface
• What happens to polypeptides after translation?


  They are folded and processed to produce proteins
• What is the role of the Golgi apparatus?


  Proteins are modified and prepared for secretion
• How are proteins transported from the RER to the Golgi apparatus?


  Inside vesicles
• What happens when vesicles fuse with the cell surface membrane?


  Proteins are secreted from the cell by exocytosis
• What types of cells have many organelles involved in protein production?


  • Hormone-producing glands
  • Enzyme-producing cells of the digestive system
• Protein Synthesis

  • DNA is stored in nucleus
  • Nucleolus produces ribosomes
  • mRNA copy of gene made (Transcription)
  • mRNA leaves nucleus via nuclear pore and attaches to ribosome on the RER
  • A chain of amino acids (polypeptide) is produced from the mRNA (Translation)
  • Polypeptides folded to produce proteins
  • Motor proteins transports the new protein down cytoskeleton to Golgi Apparatus
  • Proteins packaged & modified into vesicles
  • Vesicles fuse with cell membrane & secrete proteins (exocytosis)