Dorsal-ventral patterning within the ectoderm of the Drosophila embryo requires seven zygotic genes including sog (short gastrulation). Sog is expressed in the ventrolateral region of the embryo that gives rise to the nerve cord.
n. 1  1. The science of life and of living organisms, including their structure, function, growth, origin, evolution, and distribution. It includes botany and zoology and all their subdivisions. 2  2. The life processes or characteristic phenomena of a group or category of living organisms: the biology of fungi.
Ecology (from Greek: Î¿á¼¶ÎºÎ¿Ï, house; -Î»Î¿Î³Î¯Î±, study of) is the scientific analysis and study of interactions among organisms and their environment. It is an interdisciplinary field that includes biology and Earth science.