Mirror neurons: a definition. Description: Professor Christian Keysers explains that mirror neurons in the premotor cortex respond when we perform an action and also when we see someone else perform that action. This is similar to empathy. Transcript: Mirror neurons are a set of neurons that we discovered in the premotor cortex of the monkey.
lectin. [ 1 lekâ²tin] 2  a protein in seeds and other parts of certain plants that binds with glycoproteins and glycolipids on the surface of animal cells, causing agglutination. Some lectins agglutinate erythrocytes in specific blood groups, and others stimulate the production of T lymphocytes.
A. 1. Lecithin is any one of a group of fatty substances found in plant or animal tissues. Lecithins are obtained especially from egg yolk, soybeans, and corn. Lecithin is composed of nitrogen and phosphorus and is found especially in nerve cells and brain tissue.