Answer:
Sperm-egg interaction
Explanation:
The formation of fertilization envelope is well-studied on the model system- sea urchin. It has been shown that, the fertilization envelope is formed after the initial sperm-egg interaction from the egg surface vitelline envelope and the paracrystalline protein fraction which is derived from cortical granules. Secretion from cortical granules, prevents polyspermy.
Answer: Nutrition
Explanation: Nutrients are the essential nourishments for growth and the maintenance of life.
A turgid plant would be found in a Hypotonic enviorment