What is the major disadvantage of external Fertilization ?

In a practical test, a student has to identify the organisms in which syngamy does not occur. In those organisms the female gamete undergoes development to form new organisms without fertilization. This phenomenon is called $"X"$. Identify the organisms and the phenomenon $"X".$

What is the chromosome number in meiocyte of potato ?

$A$ – In several fungi and plants terms such as Homothalic.

$R$ – Dioecious are the terms used to describe unisexual condition.

Development of embryo from the cells of the nucellus is called