Epithellium. A tissue in vertebrates consisting of closely packed cells in a sheet with little intercellular material. It forms a membrane over the outer surfaces of the body and walls of the internal cavities (coeloms). It also forms glands and parts of sense organs. Its functions are protective, absorptive, secretory, and sensory. The types of cell vary, giving rise to squamous, cuboidal, columnar, and ciliated epithelia. Epithelium is derived from ectoderm and endoderm.

Epizoite. Non-parasitic sedentary animal living attached to another animal.

Equatorial plate. It is the plane that bisects the cell during mitosis and that lies mid-way between the poles.

Erepsin. It is an enzyme that is produced by the wall of small intestine. It digests proteins into amino acids.

Erect aerial stems.
They grow erect in air so as to expose their leaves to sun rays more favourably.

Eubacteria. The true bacteria, i.e. those typically having simple unbranched cells, rigid cells, walls, and flagella for movement.

Eugenics. Study of possibility of improving humanity by altering its genetic composition by encouraging breeding of those presumed to have desirable genes, and discouraging breeding of those presumed to have undesirable genes. It is rarely known who has which.

Euglenophyta.
A division containing algae (including Euglena) that is certain respects resemble animals more than they do plants. For example, they lack a cell was and some forms are colourless and thus ingest food since they cannot photosynthesize. Members of the Euglenophyta are unicellular and move my means of flagella; they usually inhabit fresh water. These algae are often classified by zoologists into the class Flagellata of the Protozoa.