In which of the following types of embryo sac the megaspore nuclei do not fuse to form a triploid nucleus at chalazal end

Rose plants produce large, attractive bisexual flowers but they seldom produce fruits. On the other hand a tomato plant produces plenty of fruits though they  have small flowers. Analyse the reasons for failure of fruit formation in rose.

Nitsch was able to get strawbarries of curious shapes by

Proteinaceous endosperm of maize is called

A typical angiosperm embryo Sac, at maturity …… nucleate and ……. celled.