Question

Fill up the blanks in the following paragraph by selecting the correct option.
During copulation (coitus), semen is released by the penis into the vagina and is called (i) . The ovum released by the ovary is transported to the (ii) where (iii) takes place. During fertilisation, a sperm comes in contact with the zona pellucida layer of the ovum and induces changes in the membrane that block the entry of (iv) . The secretions of the (v) help the sperm enter into the cytoplasm of the ovum.

• A. (i) - fertlisation, (ii) - fimbriae, (iii) - insemination, (iv) - eggs, (v) - middle piece
• B. (i) - insemination, (ii) - ampullary isthmic junction, (iii) - fertlisation, (iv) - additional sperms, (v) - acrosome
• C. (i) - ovulation, (ii) - ampulla, (iii) - fertlisation, (iv) - additional sperms, (v) - tail
• D. (i) - parturition, (ii) - isthmus, (iii) - insemination, (iv) - eggs, (v) - acrosome

Answer 1

Answer: (B)

(i) - insemination, (ii) - ampullary isthmic junction, (iii) - fertlisation, (iv) - additional sperms, (v) - acrosome

Insemination is the process of the release of semen by the penis into the vagina during copulation. The sperm is released into the female reproductive part. This sperm released travels through the cervix enters to the ureter and reached the junction of the isthmus and ampulla and this is the region of fertilization or fusion. the sperm and the ovum should be transported to this junction at the same time. Zona pellucida that contacts the sperm brings about changes in the egg membrane and blocks the entry of additional sperms as a result. The secretions of the acrosome a part of the head of the sperm that includes enzymes to penetrate the ovum helps the sperm enter into the cytoplasm of the ovum.

So, the correct option is '(i) - insemination, (ii) - ampullary isthmic junction, (iii) - fertilization, (iv) - additional sperms, (v) - acrosome'.