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Name __________________________
Per. ___________
Grades Nine Through Twelve
Biology/Life Sciences
Science Content Standards
Standards that all students are expected to achieve in the course of their studies.
Cell Biology
1. The fundamental life processes of plants and animals depend on a variety of chemical reactions that
occur in specialized areas of the organism's cells. As a basis for understanding this concept:
a. Students know cells are enclosed within semi-permeable membranes that regulate their interaction with
their surroundings.
c. Students know how prokaryotic cells, eukaryotic cells (including those from plants and animals), and
viruses differ in complexity and general structure.
Section 4-1: Passive Transport
1. passive transport:
2. diffusion:
3. example of diffusion:
4. concentration gradient:
5. equilibrium:
6. Substances that are able to pass through a membrane, the membrane is ___________________ to it.
7. osmosis:
8. What determines the direction in which the water molecules diffuse across a cell membrane?
9. hypotonic:
10. hypertonic:
11. isotonic:
12. Directions of Osmosis
Conditions
If solute concentration in the
environment is lower than in
the cell
If solute concentration in the
environment is higher than
in the cell
If solute concentration in the
environment is equal to that
in the cell
Environment
solution is…
Cell
solution is…
Water will
move…
Water Balance in Living Cells
13. Turgor pressure in plants is basically the
water pressure in plant cells that lends
support to plant tissues. When the turgor
pressure of a plant cell increases, does
that indicate that the cell is hypertonic,
hypotonic, or isotonic relative to its
environment? Explain your answer.
14. Why would it be dangerous for humans to drink sea water?
15. facilitated diffusion:
example:
16. Proteins that function in transport are called __________________________________.
17. How do carrier molecules transport materials across a cell membrane?
18. How might carrier molecules help maintain homeostasis during exercise, when extra energy is needed
quickly?
Section 4-2
19. active transport:
20. Explain how one common active transport system, the sodium-potassium pump, functions. (Potential
Test Essay)
21. Some molecules, such as food particles and waste materials, are too large to pass through the cell
membrane. However, the processes called ____________________ and _______________________
enable these large molecules to enter and exit the cell without passing through the cell membrane.
22. endocytosis:
23. phagocytosis:
24. exocytosis:
Cells must respond to important information and filter out unimportant information. Cell membranes
contain specialized proteins, receptor proteins that bind signal molecules and enable the cell to respond to
the signal.
25. Describe two ways that the binding of a signal molecule to a receptor protein causes a change in the
activity of the receiving cell.
26. During exercise, potassium ions build up in the fluid surrounding muscle cells. Which cell-membrane
protein helps muscle cells counteract this tendency? Explain your answer.