Cells and Membranes
Due Sunday by Midnight
Use Chapter 6 (Cells) and 7 (Membranes) as a Reference
o Complete using your textbook to find answers to the following questions. Next week we will spend going over this information and answering any questions that come up. Good luck and have fun!
Outline Grading Criteria
o Outline shows a conscientious effort to be complete and explain the questions posed. Most answers are correct.
o Student shows depth of answers by explaining, defining, and giving examples where appropriate. If there is a sentence or less for each question, this grading criteria is not met.
Cell Structure and Function (Reference: Chapter 6)
Cell theory states that all cells come from pre-existing cells (life only comes from life) and that all living things are composed of cells.
1. What is a cell?
2. Why are all cells relatively small? Even in large organisms like humans, elephants or wolves cells are small. Why?
Before answering the questions 3-5 go to the student CD, select Ch 6, activities and complete activities 6B and 6C. (Or do the activities after you answer these questions as a review). Remember that for each activity there may be more than one screen and you can click next in the upper right corner of the screen to move forward through the activity.
3. What are the major differences between prokaryotic and eukaryotic cells? Cite examples of each cell type.
4. See activity 6J and 6K on the student CD. What are the major structural and resulting functional differences, between typical plant and animal cells?
5. For each of the following organelles give their general function:
Genetic Control of the Cell
Manufacture of macromolecules
Central vacuole (plants):
(in some plants and protists)
Support, movement, and communication between cells
(in plants, fungi, and some protists)
Membrane Structure and Function (Reference: Chapter 7)
1. Describe the fluid mosaic model for plasma membranes by answering the following questions. What makes the membrane fluid? What parts constitute the mosaic? What forces hold the phospholipid molecules together? See the student CD, chapter 7, activities, 7A for a great review of the plasma membrane. Make sure to view all screens (2 of them) of the activity.
2. There are several functions of membrane proteins discussed in your book. Briefly describe each here.
3. a. What is diffusion? See activity 7C in the student CD (chapter 7).
b. Why does it occur?
c. Give an example of how diffusion would occur across a cell membrane.
c. What is equilibrium?
d. How is it related to diffusion?
e. Why is it called dynamic equilibrium?
4. What is osmosis and what causes it to occur?
5. Distinguish between the following: Use the activities 7E, 7F and 7G to review these concepts.
a. Facilitated diffusion and active transport
b. Exocytosis and endocytosis
c. Pinocytosis and phagocytosis
6. Explain the difference between active and passive transport mechanisms, giving an example of each. Hint: Discuss with respect to energy and concentration gradients.