Lamella (cell biology)

A lamella, in cell biology, is an extension of a thylakoid within a chloroplast, linking a thylakoid within one granum to one in another. They are the sites of photosystem I. Simply put, lamellae may be considered as a pair of membranes containing chlorophyll.

The middle lamella is a pectin layer which cements the cell walls of two adjoining cells together. Plants need this to give them stability and so that they can form plasmodesmata between the cells.