Question

question 5 4 pts the fusion of the egg and sperm membranes triggers several events during fertilization in sea urchins. answer the following questions about these events: a. choose the correct statement about the fast block to polyspermy: na+ ions enter the egg, biding b. which is not a correct statement about the slow block to polyspermy: a ca++ wave breaks open cor

Explanation:

In sea urchin fertilization, the fast block to polyspermy involves a rapid change in the electrical potential of the egg plasma membrane due to the influx of Na+ ions. The slow block to polyspermy is triggered by a calcium - wave that leads to the cortical reaction, where cortical granules release their contents outside the egg.

Answer:

A. The correct statement about the fast block to polyspermy is that Na+ ions enter the egg, changing the membrane potential to prevent additional sperm from fusing.
B. Without seeing the full options, in general, incorrect statements about the slow block to polyspermy might include things that mis - represent the role of the calcium wave or the cortical reaction. For example, if an option said that the calcium wave has no relation to the cortical reaction or that it does not involve the release of cortical granule contents, it would be incorrect.