Passage VI

Microtubules (MTs), which are structural components of cells, continuously elongate and shorten. An MT in catastrophe stops elongating and starts to shorten. An MT in rescue stops shortening and starts to elongate. When a cell enters mitosis from interphase, these transitions contribute to the rearrangement of the MT structure to form the mitotic spindle.

Table 1 shows the values of 3 parameters that were set in 6 computer-simulation models (CSMs A—F) of MT populations. It also shows the known values of the parameters for interphase cells and mitotic cells.

Figure 1 compares, for 3 MT characteristics, the average values predicted by the CSMs with the known average values for the 2 cell types.

Table and figure adapted from N. R. Gliksman et al. , "How the Transition Frequencies of Microtubule Dynamic Instability (Nucleation, Catastrophe, and Rescue) Regulate Microtubule Dynamics inInterphase and Mitosis: Analysis Using a Monte Carlo Computer Simulation." ©1993 by The American Society for Cell Biology.

39. According to Figure 1, for which of the 3 MT characteristics did CSM B predict a value that was closer to that of interphase cells than to that of mitotic cells ?

Answer and Explanation

Your Answer is

Correct Answer is B

Explanation

The question stem is required to be found in the three pictures in figure 1. The values ​​of CSM B and interphase cells need to be closer than the values ​​of SCM B and mitotic cells, so only the second picture meets the requirements; the vertical axis of the second picture represents average MT elongation velocity, so choose B