During oogenesis in human females, the non-cellular layer called the zona pellucida is formed by the:

Step-by-step solution

According to NCERT, during the later stages of oogenesis, the secondary oocyte forms a new non-cellular membrane called the zona pellucida surrounding itself. The oogonium and primary oocyte are earlier developmental stages that do not possess this layer. The cells of the corona radiata form the outermost cellular envelope of the ovum but are not responsible for forming the zona pellucida. Answer: Secondary oocyte