Question 1

Many antibiotics selectively kill bacteria and not mammalian cells because they block synthesis of the _______.

Accepted Answer

Antibiotics like penicillin target the bacterial cell wall, which is absent in mammalian cells, making them selectively toxic to bacteria.

Question 2

Antibiotics that block the synthesis of a cell wall would be least likely to affect cells from which organisms?

Accepted Answer

Animals do not have cell walls, so antibiotics that target cell wall synthesis would not affect them.

Question 3

If you added a drug to a suspension of bacteria that inhibited their flagella they would not be able to _____

Accepted Answer

Flagella are used for movement, so if they are inhibited, the bacteria will not be able to move.

Question 4

If you put plant cells in a hypotonic solution they swell up. The water entering the plant cell will be found primarily in the

Accepted Answer

The central vacuole is the primary storage area for water in plant cells, and it swells as water enters the cell in a hypotonic solution.

Question 5

As a plant cell grows a new cell wall the secondary wall forms:

Accepted Answer

The secondary cell wall forms between the primary cell wall and the plasma membrane, providing additional strength and support to the plant cell.

Question 6

Cells that produce a lot of lipids for membranes would have an enlarged

Accepted Answer

The smooth endoplasmic reticulum (smooth ER) is responsible for lipid synthesis, so cells that produce a lot of lipids would have an enlarged smooth ER.

Question 7

A team of researchers is studying the external structures on the dorsal (back) surface of a spider mite. The spider mite seems to be the habitat of an even smaller mite, which is approximately 0.05mm. While they can see the dorsal surface of the spider mite with their naked eye, they cannot see the mite clearly. The researchers are writing a grant to provide support for a microscope to use to study these new mites. They need to purchase a microscope with a high magnification to observe the new mites on their habitat. It is not necessary for them to observe living mites. Based on the information given, what type of microscope would you suggest?

Accepted Answer

A binocular compound light microscope is the best choice for observing small mites on the dorsal surface of a spider mite. It provides high magnification and allows the researchers to view the mites without having to kill them.

Question 8

A cytologist is examining a tissue under an electron microscope. He notices that the endoplasmic reticulum of each cell is extremely rough in appearance and he knows that the rough appearance is because of the ribosomes embedded there. He asks why there are so many ribosomes. You respond,

Accepted Answer

The rough endoplasmic reticulum is associated with protein synthesis and export, which is why there are many ribosomes present.

Question 9

A protein that is destined to reach the plasma membrane is making its way through the Golgi. At that moment, a drug was added to cells, blocking trafficking at the trans face of the Golgi. As a result, what would happen to the protein?

Accepted Answer

The protein would be stuck in the Golgi because the trans face is responsible for sorting and shipping proteins to their final destinations, including the plasma membrane. Blocking trafficking at the trans face prevents the protein from exiting the Golgi.

Question 10

If the function of centrioles was impaired in a cell, it could not:

Accepted Answer

Centrioles play a crucial role in cell division by helping to organize the mitotic spindle, which is necessary for the separation of chromosomes during cell division. If centrioles are impaired, the cell would have difficulty dividing.

Question 11

Cardiac muscle has prolonged contraction due to a sodium induced-calcium released process into the cytoplasm of the cell. Cardiac cells can communicate through pore-like channels between cells. List the junction and the organelle involved in cardiac muscle contraction?

Accepted Answer

Gap junctions allow communication between cardiac cells, and the Smooth ER (sarcoplasmic reticulum) is involved in calcium release for muscle contraction.

Quiz 4: Cell Structure