Three models for contractile-ring positioning in animal cells are presented in the schematic diagrams below. Answer the following question(s) according to these models.

-In the early embryos of Caenorhabditis elegans, defects in the formation of astral microtubules increase myosin activity throughout the cell cortex. If the spindle is forced to one side of the cell, the cortical myosin activity is observed mostly at the opposite side of the cell. Which model (1, 2, or 3) better predicts these observations? Write down 1, 2, or 3 as your answer.

Question

Three models for contractile-ring positioning in animal cells are presented in the schematic diagrams below. Answer the following question(s) according to these models.
 
-In the early embryos of Caenorhabditis elegans, defects in the formation of astral microtubules increase myosin activity throughout the cell cortex. If the spindle is forced to one side of the cell, the cortical myosin activity is observed mostly at the opposite side of the cell. Which model (1, 2, or 3) better predicts these observations? Write down 1, 2, or 3 as your answer.

Quizplus · Accepted Answer

These observations are in better agreement with the astral relaxation model (3).

Three Models for Contractile-Ring Positioning in Animal Cells Are Presented