In 1921, Sanger founded the American Birth Control League, which later became the Planned Parenthood Federation of America. In New York City, she organized the first birth control clinic staffed by all-female doctors, as well as a clinic in Harlem with an entirely African-American staff.
Cephalization is considered an evolutionary trend, whereby nervous tissue, over many generations, becomes concentrated toward one end of an organism. This process eventually produces a head region with sensory organs.Cephalization is intrinsically connected with a change in symmetry.It accompanied the move to bilateral symmetry made in flatworms, with ocelli and pinnae placed in the head region.his process eventually produces a head region with sensory organs. Cephalization is intrinsically connected with a change in symmetry. It accompanied the move to bilateral symmetry made in flatworms, with ocelli and pinnae placed in the head region.
Noun. 1. cephalalgia-pain in the head caused by dilation of cerebral arteries or muscle contractions or a reaction to drugs. head ache, headache.ache, aching-a dull persistent (usually moderately intense) pain. cluster headache, histamine headache-a painful recurring headache associated with the release of histamine from cells.oun. 1. cephalalgia-pain in the head caused by dilation of cerebral arteries or muscle contractions or a reaction to drugs. head ache, headache.