The Assignment 1. Describe the two basic functions of the plasma membrane. 2. What specific molecule is typically most abundant on each side of a plasma membrane? Explain how this influences basic membrane structure. (Note: explain means to give physiological reasons why).
3. Draw and label a section of the plasma membrane of a human cell. Your drawing should include: A phospholipid bilayer: – Each phospholipid should include at least one unsaturated, fatty acid tail. – Your plasma membrane should be at least 15-20 phospholipids in length. – Label the outside surface and the inside surface of your bilayer.
(You can write “out” on one side and “in” on the other side.) – Label a phospholipid. – tabel the hydrophilic (polar) head of a phospholipid. – Label the hydrophobic (nonpolar) tails of a phospholipid. – Make one of the phospholipids a glycolipid and Iabel it, “glycolipid.” (Make sure the glycolipid is on the correct surface of the bilayer.) Cholesterol – Draw and label two or more cholesterol molecules within the phospholipid bilayer.
Proteins and glycoproteins – Draw and label membrane proteins, including: – An integral protein that spans the membrane. – Label the polar regions of the integral protein. – Label the nonpolar region of the integral protein. – A peripheral protein. (Make sure it is on the correct surface of the bilayer.) – A glycoprotein.
(Make sure the carbohydrate portion of the glycoprotein extends from the correct surface of the membrane.) – Use a bracket and labelling lines to indicate the following regions of the plasma membrane: – polar – nonpolar Describe one or more functions of the integral proteins. Describe a function of the glycolipids and glycoproteins.