Latrunculin A is a reversible toxin that disrupts the formation of actin fibers.A culture of a particular species of diatom was treated with this toxin diluted in a buffer,while another culture was treated only with the buffer (no toxin;control).The motility of cells in each culture was assessed by counting the number of cells that were moving during a defined period of time.Which of the following conclusion statements is reasonable based on the data in the bar graph presented below?
A)Formation of actin fibers is not necessary for the movement in this species of diatom.
B)The buffer alone largely inhibited movement in this species of diatom.
C)In this species of diatom,fully formed actin fibers are necessary for movement.

Question

Latrunculin A is a reversible toxin that disrupts the formation of actin fibers.A culture of a particular species of diatom was treated with this toxin diluted in a buffer,while another culture was treated only with the buffer (no toxin;control).The motility of cells in each culture was assessed by counting the number of cells that were moving during a defined period of time.Which of the following conclusion statements is reasonable based on the data in the bar graph presented below? 
A)Formation of actin fibers is not necessary for the movement in this species of diatom. 
B)The buffer alone largely inhibited movement in this species of diatom. 
C)In this species of diatom,fully formed actin fibers are necessary for movement.

Quizplus · Accepted Answer

The bar graph shows that treatment with Latrunculin A, which disrupts the formation of actin fibers, greatly reduces the motility of cells in the culture. This suggests that actin fibers play an important role in the movement of this species of diatom. The control group also shows some decrease in motility relative to the untreated cells, but the effect is not as large as that observed in the Latrunculin A-treated group. This could indicate that some baseline level of actin fiber formation is necessary for movement, but full formation of actin fibers is required for optimal motility. Therefore, the best conclusion statement is that in this species of diatom, fully formed actin fibers are necessary for movement (Choice C).

Latrunculin a Is a Reversible Toxin That Disrupts the Formation