Question

The figure given below shows the diagrammatic representation of a human sperm. Which of the following options gives correct information about the sperm?

• A. A- Contains very little cytoplasm and has a haploid nucleus
• B. B- Contains proximal and distal centriole
• C. C- Contains enzymes required for fertilisation
• D. D- Arises from proximal centriole

Answer 1

The correct option is B B- Contains proximal and distal centriole

The sperm in human beings is a male gamete that is released in a fluid called seminal plasma before they are transferred to the female reproductive tract. Here in the given figure: A is acrosome, B is the neck, C is the middle piece and D is the tail.

A mature sperm (spermatozoa) consists of the following four parts
- Head: The head contains a haploid nucleus and very little cytoplasm. The anterior portion of the head is covered with a cap-like structure called the acrosome. It is filled with enzymes called sperm lysins (hyaluronidase, corona penetrating enzymes and zona lysins) which are required by sperm to enter inside and fertilise the egg. The acrosome is derived from the Golgi apparatus.
- Neck: It contains two centrioles, proximal and distal. Proximal centriole plays an important role during the first cleavage (mitotic division of zygote) of the fertilized ovum. Distal centriole gives rise to the axial filament of the tail.
- Middle Piece: It contains mitochondria that produce energy. Energy is needed for the movement of sperm.
- Tail: The tail is the posterior most structure that helps in the motility of the sperm.