Gabriel Gustav ValentinDied 24 May 1883 at age 72 (born 8 Jul 1810).German-Swiss physiologist who was the first person to note the digestive activity of pancreatic juice (1844)*. With Purkinje, one of his medical school teachers, he discovered in 1834 that certain cells on the inner surface of the oviduct contained cilia, tiny threadlike structures that beat in coordinated fashion independently of the nervous system and thus force the ovum to move along the tube. They investigated the occurence of ciliated cells elesewhere among vertebrates)*. In 1836, he identified the neuron nucleus and nucleolus. In 1841 he was the first to observe one type of Trypanozoma (they are now know to cause sleeping sickness). The Valentin knife was named after him.* [Image: Drawing of a neuron by Valentin, showing the protoplasm (a), the nucleus (c), the nucleolus (d) and the axonal cone (b)] |