Keskustasolun

Keskustasolun is a term used in Finnish botany to denote the central cell of the mature embryo sac (female gametophyte) in flowering plants. The central cell, referred to in Finnish as keskussolu, lies at the center of the embryo sac and typically contains two polar nuclei prior to fertilization. In botanical Finnish, the genitive form keskustasolun means "of the central cell."

Structure and location: The central cell resides in the center of the mature embryo sac within the ovule. It is usually a large cell that contains two polar nuclei, collectively called the central cell's polar nuclei. These nuclei typically fuse with a sperm nucleus after fertilization to form the endosperm nucleus.

Function and significance: The central cell participates in double fertilization, a hallmark of angiosperms. One sperm fertilizes the egg to form the zygote, while another fertilizes the central cell's two polar nuclei to produce triploid endosperm, which nourishes the developing embryo. The development and activity of the central cell are therefore essential for seed formation and seedling success.

Terminology and related concepts: The term keskustasolun appears mainly in Finnish botanical texts and discussions of embryo sac anatomy. It is closely connected to broader topics such as embryo sac structure (gametophyte), polar nuclei, endosperm formation, and double fertilization.