Which among the following is not a layer of the ovum?

Acrosome.

The correct answer is Option (3)- Acrosome.

Ovaries are the primary female sex organs that produce the female gamete (ovum).The correct sequence of the different layers of the ovule from inside to outside is: Vitelline membrane, zona pellucida, corona radiata .

The zona pellucida is a layer surrounding the egg (oocyte) and plays a role in the fertilization process.

The corona radiata refers to the layer of cells surrounding the zona pellucida of an oocyte released from the ovary during ovulation.

The acrosome is a cap-like structure located at the tip of the sperm's head. It contains enzymes that play a critical role in helping the sperm penetrate the protective layers of the egg (ovum) during the fertilization process.