Question

Mark the correct sequence of the parts labelled as A, B, C and D:–

• A. Zona pellucida – corona radiata – ovum – perivitelline space
• B. Perivitelline space – corona radiata – Primary oocyte – perivitelline space
• C. Corona radiata – zona pellucida – secondary oocyte – perivitelline space
• D. Perivitelline space – corona radiata – ovum – zona pellucida

Answer 1

The correct option is C Corona radiata – zona pellucida – secondary oocyte – perivitelline space

In mammalian egg immediately after ovulation, the layer that forms around the ovum is called corona radiata. It is formed by the granulosa cells of cumulus oophorus. Corona radiata probably increases the likelihood that the ovum will be picked up in the uterine tube.
So, the correct sequence is:
A-Corona radiata
B– zona pellucida
C – secondary oocyte
D – perivitelline space