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cell theory

the principle that all organisms are composed of one or more cells. [proposed in 1839 for animals by German physiologist Theodor Schwann (1810–1882) and for plants by German botanist Matthias Jakob Schleiden (1804–1881)]

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Psychology term of the day

February 17th 2025

mammography

mammography

n. a diagnostic procedure that uses low-dose X-ray photography to detect breast tumors or other abnormalities, either noncancerous (benign) or cancerous (malignant). The X-ray negative produced is called a mammogram.