Cell structures - Cell structures that are common to both plant

2. Below are five structures observed in cells. List the function of each structure. (5 points)
a. Chloroplasts- contain pigments and are responsible for creating food through
photosynthesis. b. Golgi apparatus- each of the individual organelles contributes to the production and
delivery of proteins, lipids, and other molecules. c. Ribosomes- This structure is composed of several folds of a membrane and is covered
with ribosomes (these bumps are why it is called "rough" endoplasmic reticulum). Once
the ribosomes receive the plans, the protein is built. d. Central vacuole
e. Rough endoplasmic reticulum

3. A microbiologist observes a single-celled organism under a compound light microscope.
This organism has a nucleus and appears to be moving by using small, hair-like
structures.
a. Based on the information in the lab, provide a probable name for this organism. (1
point)
b. Explain why the microbiologist came to this conclusion. (2 points)

4. Describe the structure and function of the cell membrane. Why does it form a
phospholipid bilayer? (5 points)

5. In the Spirogyra cells that you observed on the virtual microscope, where in the cell are
the chloroplasts located and about how many are found in a single cell? (2 points) 

6. Report the “Ending Average Volume (cubic millimeters)” and the “Percent Differences”
that you observed in the osmosis experiment for each salt solution below. (You should
have these recorded in the bottom two rows of your data Table 1 from the Lab 4
Procedures step 2b.) (8 points)
a. 0% salt solution
b. 1.75% salt solution
c. 3.5% salt solution
d. 7% salt solution

7. Describe three extraneous variables that may have impacted your osmosis results from
the experiment in Procedure 2b. (6 points)
a.
b.
c.

8. In osmosis, which direction does water move with respect to solute concentration? (2
points)

9. Using the appropriate osmotic terms (hypertonic, hypotonic, or isotonic) describe what
would happen to each organism in the following settings:
a. A single-celled freshwater protist is placed into a beaker of salt water. (3 points)
b. A salt-water snail is mistakenly put into a freshwater tank. (3 points)

10. A crisp head of Romaine lettuce was purchased from a local grocery store. The customer
who purchased the lettuce noticed that the store’s produce was constantly sprayed with
distilled (pure) water. Once home, they noticed that the leaves of the lettuce no longer
seemed as crisp and taut. Using details learned about osmosis, explain why the lettuce
was crisper at the store. (5 points)

11. People always say that leeches can be removed from the body by pouring salt on them.
Based on what was learned about osmosis in this lab, provide an explanation that
supports or refutes this information. (5 points)

12. Report the surface-to-volume area ratio for each cube from Procedure step 3a. (6 points)
a. Cube 1 b. Cube 2
c. Cube 3

13. Assume the potato cubes are cells. Which cube would be most efficient at moving
materials into and out of the cube? Briefly explain the answer. (4 points)

14. From what was observed in the potato procedure on cell size and diffusion rate
(procedure 3b), how does the rate of diffusion and surface-to-volume ratio limit cell size?
(5 points)

15. A ¼ pound hamburger and a ¼ pound meatball are cooked at the same temperature.
Using information learned about surface-to-volume ratios, provide an explanation why
one food item will cook faster? (5 points)

16. Researchers have discovered that hares tend to lose heat through their ears. Based on this
and what is known about surface-to-volume ratios, propose an explanation as to why
hares that live in hot climates (such as the desert) have large, extended ears. (5 points)

17. (Application) How might the information gained from this lab pertaining to cell
structures and diffusion be useful to you, or how can you apply this knowledge to your
everyday life as a non-scientist? The application will be graded according to the rubric
below. (20 points)