Coconut water vs white kernel: both endosperm? Plus ovary wall to pericarp and what apomixis really means
Lakshmi TripathiDropper Sample
3 Oct 2026 · 1 min read
Second attempt at NEET. Going through post-fertilisation events again, and slowly, because last time I rushed this part and fell for a few options.
NCERT says the primary endosperm nucleus (PEN) divides first, often before the zygote, and the most common type is the free-nuclear endosperm where the nuclei divide without wall formation. It gives the example of tender coconut water, and the white kernel is the cellular endosperm. So is the water really just endosperm? And what is in the "eye" of the coconut then?
Second point. After fertilisation the ovule becomes seed, integuments become seed coat, ovary becomes fruit, ovary wall becomes pericarp. Then there are false fruits like apple and strawberry, which develop from the thalamus. So an apple is a fruit but the edible part is not the ovary wall?
Third, apomixis. I understand the definition, seed formation without fertilisation. But I do not understand how it is "a seed" if there is no zygote. What does the embryo come from? And why do plant breeders want apomixis in hybrids?
I want to see what other people understand, before I memorise a wrong thing.
6 answers & replies
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[+][–]Pooja Iyer12thSample· 17d ago
Yes, the coconut water is the free-nuclear endosperm, thousands of free nuclei in a liquid. As the coconut matures, cell walls form around the nuclei and the endosperm becomes cellular, the white kernel you eat. So both are endosperm, at different stages. The embryo in a coconut is small and sits in the kernel near one of the eyes, that is why it sprouts from there. I wouldn't call the water "milk of embryo", it is nutrition for the embryo.
[+][–]Lakshmi TripathiDropperSample· 16d agoAuthor
ok that sorts the coconut. I had thought the water was something else completely. thank you pooja
[+][–]Kavya NaikDropperSample· 17d ago
Your fruit points are right. Fruit = the mature ovary. Ovary wall → pericarp (it can be fleshy like in mango or dry like in a pea pod). When a fruit forms from the ovary alone, it is a true fruit. When other parts of the flower contribute, like the thalamus in apple, strawberry and cashew (the fleshy part of cashew is the peduncle/thalamus region), they are false fruits (pseudocarps). In an apple, the edible fleshy part develops from the thalamus, and the core with seeds is the ovary part.
[+][–]Tanvi Deshmukh12thSample· 17d ago
Apomixis!! 🙂 It is a form of asexual reproduction that mimics sexual reproduction. The seeds form without fertilisation. In some species the diploid egg cell is formed without meiosis and develops into an embryo without fertilisation. In others, cells of the nucellus, which are diploid, start dividing and protrude into the embryo sac and form the embryo. That second type is why in citrus and mango you can find more than one embryo in one seed, polyembryony. NCERT even says that. So the embryo is just 2n cells from the mother plant, no male gamete needed.
[+][–]Nisha Verma12thSample· 16d ago
Why breeders care: hybrid seeds are costly because you have to make them again every season, since the progeny of a hybrid segregate in the next generation and lose the hybrid vigour. If a hybrid is made apomictic, the seeds produced are genetically identical to the mother plant, so there is no segregation, and farmers can keep using the seeds year after year. That is the point of apomixis in agriculture.
[+][–]Siddharth RaoDropperSample· 16d ago
Small thing from my own mistakes: parthenocarpy and apomixis are not the same. Parthenocarpy = fruit without fertilisation, usually seedless, like banana. Apomixis = seed without fertilisation. Many students write both as the same in assertion-reason questions. Also, in seeds that keep a leftover nucellus (black pepper, beet) it is called perisperm, different from the residual endosperm.
