Name: ___________________________________________________ Period: _____________
Homework Chapter 3-Cells: the Living Units
Date: ______________
Using your textbook, Chapter 3 pp64-112 and other outside sources. complete by _________________
1. Define cell: ______________________________________________________________________________________
2. Regardless of cell type, all cells are composed of carbon, hydrogen, nitrogen, and oxygen. Although there are over
200 different types of cells in the human body all cells have three basic parts with common functions. (p66)
_________________________ function __________________________________________________________
_________________________ function __________________________________________________________
_________________________ function __________________________________________________________
3. Below is a portion of a diagram of a plasma membrane. Color the circles and the structures. Answer the questions.
1) What is the model of the membrane structure called? ____________________
_________________________
___________________
2) What is the function of cholesterol in the plasma membrane? ______________________________________
_____________________________________
3) What is the carbohydrate rich area indicated by A _______________________________________________
4) Which area, B or C, indicates the nonpolar region of the phospholipid molecule? ____________
5) Is the nonpolar region hydrophobic or hydrophyillic? ____________________________________________
6) Which label, D or E, indicates a peripheral protein? _____________
7) Which label, D or E, indicates an integral protein? _____________
8) What is the purpose of the glycocalyx? (pg69) ___________________________________________________
__________________________________________________________________________________________________
4. Label the specializations in the plasma membrane diagram below. See p69- 70 in text. Answer questions.
1) What is the purpose of microvilli? ____________________________________________________________
2) What type of cells usually have microvilli? Give an example. ______________________________________
____________________________________
3) What 3 factors help hold cells together?
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
4) Which cell junction is impermeable? ________________________________________
5) Which cell junction is button-like? __________________________________________
6) Which cell junction allows for communication between adjacent cells? ____________________________
7) Where are gap junctions found and Why? _____________________________________________________
________________________________________________________________________________________________
5. Use pages 70-72 in your text to do the following activity and answer the questions. Below is a simplified diagram of
the plasma membrane with various channel proteins. Channel protein A is a pore; B represents and ATP dependent
solute pump; and C is a passive transport protein. Identify the structures by coloring.
Cell Interior
O2
C O2
Na+
Glucose
K+
Amino acid
Now use arrows to show how the substances listed would move through the cell. Use the arrow to indicate whether it
would move into or out of the cell. If the substance is actively transported use a red arrow. Answer questions.
1. Which substances move passively through the lipid part of the membrane?___________________________
2. Which substances use a passive transport protein? ______________________________________________
3. Which substances move through a pore? ______________________________________________________
4. Which substance need a solute pump to move through the membrane? _____________________________
6. Uses the choices below to characterize each statement.
A. Bulk phase endocytosis
B. Diffusion, dialysis
C. diffusion, osmosis
D. Exocytosis
E. Filtration
F. Phagocytosis
G. receptor mediated endocytosis
H. solute pump
_______1. Engulfment processes that require ATP
_______2. Driven by molecular energy
_______3. Driven by hydrostatic (fluid) pressure; usually blood pressure
_______4. Moves down with the concentration gradient
_______5. Moves up against the concentration gradient; requires a carrier
_______6. Uses a clathrin coated vesicle or coated pit
_______7. Typically involved couples systems like symports or antiports
_______8. Examples of vesicular transport
_______9. A means of bringing large particles into the cell
_______10. Used to eject waste and secrete cell products
7. Use page 74 in your text to help answer the following questions. The figure below shows three microscopic fields
with red blood cells. Arrows indicate direction of net osmosis. Color code the diagrams and answer the questions.
A
1. Name the type of tonicity in
B
C
A________________________ B_______________________ C___________________
2. Term that describes cell shape A________________________ B_______________________ C___________________
3. What does isotonic mean? _________________________________________________________________________
4. Why are the cells in C bursting? _____________________________________________________________________
5. What is the difference between tonicity and osmolarity? _________________________________________________
__________________________________________________________________________________________________
8. Use page 66 to review the structures in a generalized cell.
1. Define cytosol: _________________________________________________________________________________
2. What are lysosomes? ____________________________________________________________________________
3. What is the function of peroxisomes? _______________________________________________________________
4. What is a cytoskeleton? _________________________________________________________________________
5. What is the function of the Golgi apparatus? ________________________________________________________
6. What is the function of mitochondria? _____________________________________________________________
7. What are centrioles? ___________________________________________________________________________
8. What is the difference between cilia and flagella? _____________________________________________________
________________________________________________________________________________________________
9. What is the difference between DNA, chromatin, and chromosomes? ______________________________________
__________________________________________________________________________________________________
__________________________________________________________________________________________________
10. What is the function of ribosomes? _________________________________________________________________
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