Q.

The function of copper ions in copper releasing IUDs is                  [2017]

1 they inhibit gametogenesis  
2 they make uterus unsuitable for implantation  
3 they inhibit ovulation  
4 they suppress sperm motility and fertilising capacity of sperms.  

Ans.

(4)

Copper releasing IUDs (i.e., CuT, LNG-20) are placed in the uterus of the females. They are efficient birth control methods. Copper ions released by them suppress motility and fertilising capacity of the sperms.