Gregor Mendel pod shape, unripe pod color, flower location, and plant height. He first focused on seed shape, which was either angular or round. Between 1856 and 1863 Mendel cultivated and tested some 28,000 plants, the majority of which were pea plants ("Pisum sativum"). This study showed that, when true-breeding different varieties were crossed to each other (e.g., tall plants fertilized by short plants), in the second generation, one in four pea plants had purebred recessive traits, two out of four were hybrids, and one out of four were purebred dominant. His experiments led him to make two generalizations, the Law of
Catholic Church and health care them clergymen) made a number of important discoveries which aided the development of modern science and medicine. Saint Albert the Great (1206–1280) was a pioneer of biological field research; Desiderius Erasmus (1466-1536) helped revive knowledge of ancient Greek medicine, Renaissance popes were often patrons of the study of anatomy, and Catholic artists such as Michelangelo advanced knowledge of the field through sketching cadavers. The Jesuit Athanasius Kircher (1602 – 1680) first proposed that living beings enter and exist in the blood (a precursor of germ theory). The Augustinian Gregor Mendel (1822-1884) developed theories on genetics for the first time. As