Das Keimplasma (English spelling)

…He first studied chemistry and medicine at the University of Göttingen, and became a doctor, but then re-entered the University of Giessen, where he mainly studied insect development, and then worked at the Zoological Institute of the University of Freiburg until his retirement in 1912. His eyesight deteriorated due to straining his eyes during his microscopic research, so he devoted himself to theory in the latter half of his life, which bore fruit in 1892 with the theory of the germ plasm. According to this theory, only the nuclei of germ cells retain all the determining factors for traits, but in somatic cells, the determining factors are distributed unevenly as development progresses, and tissue differentiation ultimately occurs under the control of a small number of determining factors, completely denying the inheritance of acquired traits. …

*Some of the terminology referenced in "Das Keimplasma" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…初めゲッティンゲン大学で化学と医学を学び，いったんは医者になったが，ギーセン大学に再入学しおもに昆虫の発生を研究し，その後1912年の定年までフライブルク大学動物学研究所に勤めた。顕微鏡研究で目を酷使し視力が衰えたため後半生は理論面に力を注ぎ，1892年の《生殖質説Das Keimplasma》として結実した。これによると，生殖細胞の核だけはすべての形質の決定因子を保持し続けるが，体細胞は発生の経過とともに決定因子が不均等に分配されてゆき，最終的に少数の決定因子の支配によって組織分化が起こるとされ，獲得形質の遺伝は全面的に否定された。…

※「《Das Keimplasma》」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報