viljastuvad

Viljastuvad iseseisev Estonian verb form meaning “to become fertilized” or “are fertilized.” It is the third-person plural present form of viljastuda, an intransitive verb used to describe a state or process in which a gamete or cell undergoes fertilization. In practical use, nad viljastuvad would translate as “they become fertilized” or “they are fertilized,” and the form appears in educational and scientific contexts when discussing reproduction.

In biological text, viljastuvad can refer to the fertilization of eggs or ovules in both plants and animals. In animals, fertilization typically involves a sperm uniting with an oocyte to form a zygote, triggering embryonic development. In plants, fertilization often involves pollen reaching the ovule, with processes such as pollen tube growth creating a zygote and, in many flowering plants, endosperm formation as part of seed development. Angiosperms exhibit a form of fertilization known as double fertilization, where two fertilization events give rise to both the embryo and the endosperm.

Viljastumise as a process is usually described by the noun viljastamine, while fertilized cells or structures may be referred to as viljastunud (fertilized) or viljastunud munarakk (fertilized egg). The term viljastuvad therefore appears in sentences outlining ongoing or completed fertilization events, often in biological diagrams, textbooks, and research descriptions.

Related concepts include fertilization in general (viljastumine), fertilized eggs or zygotes, and the broader context of seed and reproductive development in plants and animals.