Read the paragraph and answer the Question given below:
Humans are sexually reproducing and viviparous. The male reproductive system is composed of a pair of testes the male sex accessory ducts and the accessory glands and external genitalia. The female reproductive system consists of a pair of ovaries a pair of oviducts, a uterus, a vagina, external genitalia and pair of mammary glands. The reproductive cycle of female primates is called menstrual cycle. Menstrual cycle starts only after attaining sexual maturation (puberty). Coitus followed by fertilization leads to formation of zygote. After 9 months of pregnancy, the fully developed foetus is ready for delivery.
The nucleus is present in _______ of human sperm.
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Head
Option (1) Middle piece — Incorrect. The middle piece has numerous mitochondria. They produce the energy for the movement of the tail.
Option (2) Acrosome — Incorrect. The acrosome is a cap over the front of the nucleus. It is filled with enzymes that help in fertilisation.
Option (3) Head — Correct. The human sperm has a head, neck, middle piece and tail. The head contains an elongated haploid nucleus, covered at its front by the acrosome.
Option (4) Tail — Incorrect. The tail moves the sperm (sperm motility), which is needed to reach the ovum. It has no nucleus.
Note: The passage is taken from NCERT. NTA has put lines of the NCERT text together to make it. Most CUET (UG) questions come straight from NCERT, so study the book line by line, including figures and their titles.
NCERT Extract:
Gametogenesis – “… Let us examine the structure of a sperm. It is a microscopic structure composed of a head, neck, a middle piece and a tail (Figure 2.6). A plasma membrane envelops the whole body of sperm. The sperm head contains an elongated haploid nucleus, the anterior portion of which is covered by a cap-like structure, acrosome. The acrosome is filled with enzymes that help fertilisation of the ovum.”
Figure 2.6 Structure of a sperm