Question

Differentiate between Mesogamy and Porogamy.

Answer 1

Hint: Both Mesogamy and porogamy are patterns of fertilisation followed by different plants. These methods are determined by the pathway taken by the pollen tube to enter into the ovary sac.

Complete answer
Fertilisation is a process in which male gamete (pollen grain) fuses with female gamete (egg) to form a diploid zygote. This process begins from stigma and finishes within the ovary sac. As the anther reaches the stigma, it starts germinating and a pollen tube starts growing inside the pistil that later carries the anther towards the ovary. Now, there are two openings in the ovary sac for the pollen tube to enter and drop the anther. Those are the micropylar end and integumentary end. Later, the anther converts into haploid nucleus and combines with the haploid egg nucleus inside the ovule (the inner sac of ovary) to form diploid zygote.

Parameters	Mesogamy	Porogamy
Definition	It is the process of fertilisation in which a pollen tube enters the ovary sac through the integuments.	It is the process of fertilisation in which a pollen tube enters the ovary sac through a micropyle.
Occurrence	It is a comparatively rare process to be observed amongst plants.	It is the typical process of fertilisation followed by most of the plants.
Pathway	It is an indirect pathway for entering into the ovule.	It is the direct pathway for entering into the ovule.
Examples	All cucurbit crops like Pumpkin.	Flowering plants like lily.

Note:
In angiosperms, that is flower yielding plants, two fertilisations take place at a time inside the ovule. Anther splits into two nuclei out of which one combines with the egg cell to form zygote while the other one combines with polar nuclei to form endosperm (the food material of the embryo).