GMAS Biology Practice Test

The concept being tested is inheritance of acquired characteristics—the idea that traits developed or modified during an organism’s life could be passed on to its offspring. This was proposed by Jean-Baptiste Lamarck, who argued that if an organism used a feature more and it changed, that change could be inherited by its descendants. A classic example is the idea that giraffes stretched their necks to reach higher leaves and, over generations, necks became longer. This view contrasts with Darwin and Wallace’s idea of natural selection, where evolution happens because individuals with heritable variation survive and reproduce more, not because traits acquired during life are transmitted. It also differs from Mendel’s work on genetics, which shows inheritance operates through discrete units of heritable information (genes) rather than acquired changes. In modern biology, Lamarck’s mechanism isn’t supported as a general rule, though some limited epigenetic effects can influence gene expression in offspring in specific contexts, they don’t constitute the classic inheritance of acquired characteristics.