Name:
Hour:
Cardinal Heights
Biology-R
CHAPTER 4:
Membranes
pgs. 220-221
1. What is the job of the cell membrane?
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2. Why must a cell membrane sometimes be impermeable?
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3. Why is it important that our cell membranes be selectively permeable?
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4. Explain the 2 major parts of the lipid bilayer.
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5. Apply it! Why is this structure important for our cell membranes to function properly?
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Draw a picture and label the following parts: hydrophobic tails, hydrophyllic heads, protein
channel, carbohydrate.
6. What role do proteins have in transporting molecules in and out of the cell?
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7. Why can’t ions like salt, pass directly through the membrane if they are small? How do
they get in and out of the cell then?
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Fill in the following chart using your reading and reading guide. You need to understand these
vocabulary terms in order to fully understand the reading and/or biology content.
Formal Definitions – Come from the reading or your class notes. This is the scientific
definition.
“Own Words” Definition – Describe what this term means in your own words, try to make it
easier for you and others to understand.
Sentence example – Create a sentence that demonstrates you understand what the word means.
“Hominids are sexy,” is not a good sentence example, I am not sure you understand what
hominids means. (Yes, someone really did do that last year!)
Visual Representation – Create some sort of drawing that illustrates your understanding of the
term. Get creative here…stick figures are allowed 
Word
Selectively
Permeable
Impermeable
Ions
Hypotonic
Isotonic
Hypertonic
Formal
Definition
“Own Words”
Definition
Sentence
Example
Visual
Representation