Biology 9700 · AS & A Level · Proteins

Proteins — practice question

Lactase is an enzyme located in the membranes of epithelial cells that line the small intestine. This enzyme consists of a single polypeptide that folds into three regions. What type of amino acid would be present in each of these three regions?

  • Aoutside cell: hydrophilic; inside the membrane: hydrophobic; inside the cell: hydrophilic
  • Boutside cell: hydrophilic; inside the membrane: hydrophobic; inside the cell: hydrophobic
  • Coutside cell: hydrophobic; inside the membrane: hydrophilic; inside the cell: hydrophobic
  • Doutside cell: hydrophobic; inside the membrane: hydrophobic; inside the cell: hydrophilic

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