Eastern Intermediate High School
Honors Biology
Name:___________________________
Mod:_______ Date:________________
Chapter 3 – The Plasma Membrane
Worksheet - The Plasma Membrane and Homeostasis
Directions: Color and label the diagram below:
1. Color the hydrophilic regions green and the hydrophobic regions yellow .
2. Circle each layer in the membrane.
3. Label the polar regions in the diagram.
4. Label the non-polar regions in the diagram.
5. Sketch a protein molecule in the membrane.
6. Sketch a cholesterol molecule in the membrane.
Proteinintegrin
Polar
hydrophilic
Non-Polar
hydrophobic
Non-Polar
hydrophobic
Polar
hydrophilic
7. Which types of molecules are found in the plasma membrane?
______________________phospholipids and proteins________________________________
__________________________________________________________________________
8. What role does cholesterol play in cell membrane fluidity?
_____________helps keep the membrane fluid by keeping tails separated___________________
__________________________________________________________________________
(Over)
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Directions: Identify the following structures in the diagram below:
9.
Integrins: ___B__
10.
Cholesterol: ___E__
11.
Carbohydrates: __D___
12.
Glycoproteins: __C___
13.
Phosphate Group: ___F__
14.
Fatty Acid Chain: ___G__
15.
Phospholipid Bi-Layer: __A___
16.
Explain the importance of glycoproteins and carbohydrates on the surface of cells?
______________markers, receptors, “flags”________________________________________
__________________________________________________________________________
17.
Explain how the phospholipid bilayer serves as a selectively permeable barrier?
________only some molecules may pass through the barrier – non-polar and small are best! _____
__________________________________________________________________________
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