Question 1

Vinblastine,a drug that inhibits microtubule polymerization,is used to treat some forms of cancer.Cancer cells given vinblastine would be unable to

Accepted Answer

Vinblastine inhibits microtubule polymerization which is involved in the formation of the spindle fibers necessary for the separation of chromosomes during cell division. Therefore, cancer cells given vinblastine would be unable to separate chromosomes during cell division.

Question 2

-The differences among the three categories of cytoskeletal elements outlined in the table above would suggest that each of the following has specialized roles.Which of the following is a correct match? (All three elements are involved in the maintenance of cell shape.)

Accepted Answer

Microtubules are involved in chromosome movement during cell division, as they form the mitotic spindle which helps separate chromosomes.

Question 3

When a potassium ion (K⁺)moves from the soil into the vacuole of a cell on the surface of a root,it must pass through several cellular structures.Which of the following correctly describes the order in which these structures will be encountered by the ion?

Accepted Answer

When a potassium ion (K⁺) moves from the soil into the vacuole of a cell on the surface of a root, it first encounters the primary cell wall, then the plasma membrane, followed by the cytoplasm and ultimately reaches the vacuole. Therefore, option C is the correct choice. It is important to note that lysosomes are not involved in the transport of potassium ions from the soil into the vacuole.

Question 4

All of the following serve an important role in determining or maintaining the structure of plant cells.Which of the following are distinct from the others in their composition?

Accepted Answer

Plant cell walls are distinct because they are primarily composed of cellulose, a carbohydrate, whereas the other structures listed are composed of proteins.

Question 5

Movement of vesicles within the cell depends on what cellular structures?

Accepted Answer

Movement of vesicles within the cell depends on microtubules and motor proteins. Microtubules provide tracks for vesicles to move along, while motor proteins use energy from ATP to move the vesicles along the microtubules.

Question 6

If an individual has abnormal microtubules due to a hereditary condition,in which organs or tissues would you expect dysfunction?

Accepted Answer

Microtubules are important for the formation and function of cilia and flagella. Therefore, dysfunction would be expected in tissues or organs that contain these structures, such as sperm, larynx, and trachea. Dysfunction in other tissues/organs such as limbs, heart, and areas with contraction may be related to other cytoskeletal abnormalities.

Question 7

Motor proteins provide for molecular motion in cells by interacting with what types of cellular structures?

Accepted Answer

Motor proteins interact with cytoskeletal structures such as microtubules and actin filaments to generate molecular motion in cells.

Question 8

Which type of organelle is found in plant cells but not in animal cells?

Accepted Answer

Plastids, which include chloroplasts, are found only in plant cells and are responsible for processes such as photosynthesis.

Question 9

The cell walls of bacteria,fungi,and plant cells and the extracellular matrix of animal cells are all external to the plasma membrane.Which of the following is a characteristic common to all of these extracellular structures?

Accepted Answer

These extracellular structures are indeed constructed of polymers that are synthesized in the cytoplasm and then transported out of the cell. This is a common characteristic among the cell walls of bacteria, fungi, and plant cells, as well as the extracellular matrix of animal cells.

Question 10

In a liver cell detoxifying alcohol and some other poisons,the enzymes of the peroxisome remove hydrogen from these molecules and

Accepted Answer

The peroxisome enzymes remove hydrogen from alcohol and other poisons and transfer them to oxygen molecules, generating hydrogen peroxide. The hydrogen peroxide is then broken down by catalase enzymes present in the peroxisome itself, protecting the cell from being damaged by the harmful substances.

Question 11

Cytochalasin D is a drug that prevents actin polymerization.A cell treated with cytochalasin D will still be able to

Accepted Answer

The answer of Cytochalasin D is a drug that prevents...

Question 12

A cell has the following molecules and structures: enzymes,DNA,ribosomes,plasma membrane,and mitochondria.It could be a cell from

Accepted Answer

All of these structures and molecules are found in eukaryotic cells, which include organisms such as fungi, protists, plants, and animals. Bacteria typically do not have mitochondria or a nucleus containing DNA, and plants have additional structures such as cell walls and chloroplasts. Therefore, the best choice is C, nearly any eukaryotic organism.

Question 13

How does the cell multiply its peroxisomes?

Accepted Answer

Peroxisomes multiply by growing and then dividing, a process similar to binary fission seen in bacteria. This allows the cell to increase the number of peroxisomes in response to needs without requiring external input or complex assembly processes.

Question 14

Why isn't the mitochondrion classified as part of the endomembrane system?

Accepted Answer

The mitochondrion is not derived from the endoplasmic reticulum (ER) or Golgi apparatus, which are key components of the endomembrane system. While it is involved in many cellular processes, including energy production and calcium signaling, it is not part of the ER or Golgi membrane network.

Question 15

Centrioles,cilia,flagella,and basal bodies have remarkably similar structural elements and arrangements.Which of the following hypotheses is most plausible in light of such structural similarities?

Accepted Answer

The fact that centrioles, cilia, flagella, and basal bodies have similar structural elements and arrangements suggests that they are all related and have a common evolutionary origin. The most plausible hypothesis is therefore that cilia and flagella arise from the centrioles, which serve as the organizing center for microtubule formation. This is supported by the observation that cilia and flagella grow out of centrioles, and that they share many of the same proteins and motor proteins involved in their movement.

Question 16

Which of the following contain the 9 + 2 arrangement of microtubules,consisting of nine doublets of microtubules surrounding a pair of single microtubules?

Accepted Answer

Only flagella and motile cilia contain the 9 + 2 arrangement of microtubules with nine doublets of microtubules surrounding a pair of single microtubules. Centrioles and basal bodies also have this arrangement, but they do not contain the characteristic protruding structures of motile cilia and flagella. Primary (nonmotile) cilia do contain microtubules, but they only have a 9 + 0 arrangement with nine doublets of microtubules and no central pair.

Question 17

Cells require which of the following to form cilia or flagella?

Accepted Answer

Centrosomes are required for the formation of cilia or flagella, as they act as a microtubule-organizing center from which microtubules extend to form the structural basis of the cilia or flagella. Laminin is a extracellular matrix protein and not directly involved in the formation of cilia or flagella. Actin and intermediate filaments are not involved in the formation of cilia or flagella. Secretory vesicles are involved in exocytosis and are not directly involved in the formation of cilia or flagella.

Question 18

The smallest cell structure that would most likely be visible with a standard (not super-resolution)research-grade light microscope is

Accepted Answer

Mitochondria are typically 0.5-1.0 micrometers in size, which is within the resolution limit of a standard light microscope (about 200 nanometers), making them the smallest structures listed that are likely to be visible. Ribosomes, microtubules, microfilaments, and nuclear pores are all smaller than this limit and would not be clearly visible without more advanced microscopy techniques.

Question 19

What do the cell walls of plants and the extracellular matrix of animal cells have in common?

Accepted Answer

Both the cell walls of plants and the extracellular matrix of animal cells have functional connections with the cytoskeleton inside the cell. In plants, the cell wall is connected to the cytoskeleton via proteins called plasmodesmata, while in animal cells, the extracellular matrix is connected to the cytoskeleton via integrins. These connections allow for coordination between the interior and exterior of the cell and play important roles in cell signaling and communication.

Question 20

Which of the following statements about the cytoskeleton is true?

Accepted Answer

The answer of Which of the following statements about the...

Quiz 6: A Tour of the Cell