Perisperm is $:-$

In castor, the proliferation of the outer integumentary cells at the micropylar region forms a structure known as the caruncle. What is the primary function of this structure?

Which one of the following fruits is parthenocarpic?

In which of the following,thalamus contributes to fruit formation?

Differentiate between:
$(a)$ Hypocotyl and epicotyl;
$(b)$ Coleoptile and coleorhiza;
$(c)$ Integument and testa;
$(d)$ Perisperm and pericarp.

Testa and tegmen of the seed coat represent