The endosperm of some species take up water readily at germination. It consists mainly of hemicellulosic polysaccharides. The composition of these is investigated. Apart from acting as a reserve material the endosperm of some species have an ecological function. The stage of development of the vascular tissue of the embryo prior to germination is investigated by light- and electron microscopy.
Extrafloral nectaries appear on the margins of the leaf petioles at the base of the leaf lamina.
The adaxial epidermis develop into glandular cells separated from the petiole epidermis by mucilaginous cells. The nectar is secreted under the cuticle. The structural features is sought related to function of the nectaries. Glandular epidermis, mucilage cells, cuticle, vascular tissue. Alstroemeriaceae og Ruscaceae.