- Antibiotics are drugs used to treat bacterial infec-
tions. Some antibiotics disrupt the process of pro-
tein synthesis within bacteria. Others block DNA
synthesis and cell division by the bacteria. Still oth-
ers inhibit cell wall synthesis by the bacteria. If all
antibiotics worked equally well against bacteria,
would any of those mentioned here be better than
the others, from the patient’s perspective? Explain
your answer. - A new lab instructor wants his students to see liv-
ing cells. He puts a drop of his own blood on a glass
slide, adds two drops of distilled water “so the cells
will be spread out and easier to see,” puts on a
cover glass, and places the slide under a microscope
on high power. He invites his students to see living
red blood cells. The students claim that they can-
not see any cells. Explain what has happened. How
could this have been prevented?
3. A friend asks you how DNA can be used to identify
someone, and why it is called a “DNA fingerprint.”
What simple explanation can you give?
4. A cell has extensive rough ER and Golgi apparatus.
Give a brief explanation of its function. A second
cell has microvilli and many mitochondria. Give a
brief explanation of its function.
5. A bacterial toxin is found to cause harm by first fit-
ting into a receptor on human cell membranes;
once the toxin fits, the cell will be destroyed. A
medication is going to be made to stop this toxin,
and can work in one of two ways: The drug can
block the receptors to prevent the toxin from fit-
ting in, or the drug can act as decoy molecules
shaped like the receptors. Which one of these
might be better, and why?
66 Cells
FOR FURTHER THOUGHT