Question

What allows the sperm to get through the protective

covering of the egg? How does the egg change upon
fertilization? Why are the changes in the egg important?

Answer 1

The egg is covered in a thick outer coating known as the zona pellucida, a layer of carbohydrate-covered proteins that surrounds the plasma membrane. The zona pellucida helps protect the egg and is responsible for mediating the initial meeting of sperm and egg.

An egg changes dramatically at fertilization. These changes include its developmental potential, its physiology, its gene expression profile, and its cell surface. ... We highlight the major cell surface changes that occur in echinoderms, one of Just's preferred research organisms.

Step-by-step explanation:

Answer 2

The sperm releases substances that allow the sperm to enter the egg. Changes happen in the egg that prevent other sperm from entering. This is important so that the total chromosome count of the zygote is 46.

Step-by-step explanation: