Question

This amongst the following statements is incorrect. Human spermatozoa usually
(a) moves with the help of their tails
(b) Contains enzyme in their head which aids in penetration of the ovum
(c ) are released in large numbers after a few days of abstinence
(d) at a concentration of 1 million/ml of ejaculate will fertilize the ovum

Answer 1

Hint:
The midpiece contains mitochondria arranged in a spiral, which provide the energy (ATP) for the locomotion of sperm to the site of fertilization and sperm metabolism.

Complete step by step answer:
Sperm contains a nucleus with 23 highly condensed chromosomes. Covering the anterior two-thirds of the nucleus is the acrosome- a cap-like vesicle filled with enzymes that help sperm penetrate secondary oocytes to bring about fertilization. Among the enzymes are hyaluronidase and proteases. The tail of the sperm is subdivided into four parts: neck, midpiece, principal piece, and end piece. The neck Is the constricted region just behind the head that contains centrioles. The microtubules from the centriole comprise the remaining part of the tail. It is not necessary to have a concentration of 1 million/ml of sperm to be ejaculated to fertilize the ovum.
Hence the correct answer is, at a concentration of 1 million/ml of ejaculate will fertilize the ovum.

Option ‘D’ is correct

Note:
A sperm is about 60 micrometres long and contain several structures that are highly adapted for reaching and penetrating a secondary oocyte. The major part f the sperm is the head, and the tail, the flattened, pointed head of the sperm is about 4-5 micrometre long.