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.
Leptin is a hormone that is tied closely to regulating energy intake and expenditure, including appetite, metabolism and hunger. It is the single most important hormone when it comes to understanding why we feel hungry or full. When present in high levels, it signals to our brain that weâre full and can stop eating.