Download [Template] Cell Membrane and Color copy

The Cell Membrane and Transport of Molecules
Directions: Color the diagram and then read the text and answer the questions below.
Color:
Phospholipid heads-Blue
Protein channels-Green Receptor Protein-Purple
Fatty acid tails-Red
Protein Pumps-Yellow
Receptor Protein for binding with
hormones and neurotransmitters
The cell membrane is “selectively permeable”, which means that the cell membrane has some control over what
can cross it so that only certain molecules either enter or leave the cell. Passive Transport is the way that small
molecules can cross the membrane without any additional energy being expended. In Passive Transport,
molecules move from an area of high concentration to low concentration. These molecules could be water
molecules, ions, oxygen gas, and carbon dioxide gas. Active Transport moves small molecules across the
membrane, but for these molecules to move, they need energy, because they cannot move by diffusion! Active
transport moves molecules from where they are in low concentration to where they are in high concentration;
that means that it builds up a high concentration of the molecule. Receptor proteins in a cell membrane bind to
substances like hormones or neurotransmitters and cause a change in the activity of the cell. But what about
larger molecules, like proteins? Large molecules move across cell membranes using a vesicle - the cell membrane
folds in and wraps the molecule forming a membrane vesicle around it. Large molecules will either move into
the cell in a vesicle by endocytosis, or they will exit the cell in a vesicle by exocytosis. You know that “cyto-”
means “cell”, and if you put that together with “endo-“ meaning “into” or with “exo-“ meaning “out” or “exit”
you know if a molecule is moving in or out.
Answer the following questions on loose paper and staple them on the back of this page.
Diagram questions - Review the diagram to find these answers:
1. The cell membrane is called a phospholipid bilayer, explain why.
2. What are the three specific types of proteins found in the cell membrane called?
3. Which proteins are used for facilitated diffusion?
4. Which proteins are used for active transport?
Reading questions - Review the paragraph above to find these answers.
5. Explain what selectively permeable means.
6. What is passive transport?
7. What do receptor proteins do?
8. What is active transport?
9. What is a vesicle?
10. What is endocytosis? What would a cell use endocytosis for?
11. What is exocytosis? What would a cell use exocytosis for?