Category: E

A group of hereditary disorders involving tissues and structures derived from the embryonic ectoderm. They are characterized by the presence of abnormalities at birth and involvement of both the epidermis and skin appendages. They are generally nonprogressive and diffuse. Various forms exist, including anhidrotic and hidrotic dysplasias, focal dermal hypoplasia, and aplasia cutis congenita. Ectodermal…

The outer of the three germ layers of the embryo. The outermost layer of differentiated cells in the embryo from which the nervous system, sense organs, oral cavity, and skin eventually develop. The outer layer of an early embryo. In the embryo, outside layer of cells from which the nervous system, skin, special sense organs…

The outer wall of a pollen grain (the inner wall being the intine), the sculpturing and internal layering of the exine usually provide useful taxonomic characters.  

(In ferns) without a membrane covering the sorus. Without an indusium, in ferns.  

Coming off in large, thin-layered flakes.  

Curved away from the central part [unusual term, not recommended].  

Running through to the apex and beyond, as a mucro; (In ferns) veins from the midrib of a pinna or pinnule running towards the base of the sinus between the lobes of that pinna or pinnule, usually joined by lateral veins from other vein groups; With the stem remaining in the centre, the other parts…

Hollowed out.  

Without auricles.