Sanakirja.org

Määritelmät

Substantiivit

1. A group of four things.
2. (chemistry) A tetravalent atom or radical.
3. (biology) Two pairs of sister chromatids (a dyad pair) aligned in a certain way and often on the equatorial plane during the meiosis process.
4. (biology) Group of four haploid and immature pollen grains in tetrahedral fashion produced by meiotic microsporogenesis.