Question

Describe the structure of human sperm and ovum with diagrams.

Hint:

The sperm is designed for mobility and genetic delivery, while the ovum is designed for nutrient storage and genetic contribution to fertilization.

Answer 1

The structure of human sperm and ovum are essential for reproduction, and they are specifically adapted to perform their respective roles in fertilization.
1. Structure of Human Sperm:
Human sperm consists of three main parts: the head, the midpiece, and the tail (flagellum). Each part plays a crucial role in the sperm's function.
- Head: The head contains the nucleus, which holds the sperm's genetic material (23 chromosomes). The tip of the head, called the acrosome, contains enzymes that help the sperm penetrate the ovum during fertilization.
- Midpiece: The midpiece is rich in mitochondria, which provide energy for the sperm's movement. It connects the head to the tail.
- Tail (Flagellum): The tail is responsible for the sperm's motility, allowing it to swim toward the egg. It moves in a whip-like fashion to propel the sperm.
2. Structure of Human Ovum (Egg Cell):
The human ovum is a large, spherical cell and contains the female's genetic material (23 chromosomes). It consists of the following parts:
- Nucleus: The nucleus contains the egg's genetic material, which combines with the sperm's genetic material during fertilization to form a zygote.
- Cytoplasm: The cytoplasm surrounds the nucleus and contains nutrients and organelles needed for the early stages of embryo development.
- Zona Pellucida: A glycoprotein layer surrounding the egg that plays a role in fertilization by allowing only one sperm to enter the egg.
- Corona Radiata: A layer of cells that surrounds the zona pellucida and provides the egg with protection and nutrients.