Date | Text | |
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29 May 1897
Julius von Sachs |
death Julius von Sachs Died 29 May 1897 at age 64 (born 2 Oct 1832). (Ferdinand Gustav) Julius von Sachs was a German botanist studying plant physiology, nutrition, and tropism (response to environmental stimuli). He discovered transpiration: that the absorbed water moves in tubes in the plant walls without the cooperation of living cells. In 1865, Sachs discovered chlorophyll, the green substance of plants; that it is located in special bodies within plant cells (later called chloroplasts); that glucose is made by the action of chlorophyll; and that the glucose is usually stored as starch. Sachs studied the formation of growth rings in trees, the role of tissue tension in promoting organ growth. He invented the clinostat to measure the effects of such external factors as light and gravity on the movement of growing plants. His work was a significant contribution to the knowledge of plant physiology during the second half of the 19th century. |