AP BIOLOGY

Detailed explanation-1: -By the late 1830s, botanist Matthias Schleiden and zoologist Theodor Schwann were studying tissues and proposed the unified cell theory. The unified cell theory states that: all living things are composed of one or more cells; the cell is the basic unit of life; and new cells arise from existing cells.

Detailed explanation-2: -Matthias Jacob Schleiden was a German botanist who, with Theodor Schwann, cofounded the cell theory. In 1838 Schleiden defined the cell as the basic unit of plant structure, and a year later Schwann defined the cell as the basic unit of animal structure.

Detailed explanation-3: -What did Schleiden and Schwann both discover individually? All living things are composed of one or more cells.

Detailed explanation-4: -All living organisms are made up of one or more cells, which are considered the fundamental units of life. Even unicellular organisms are complex! Inside each cell, atoms make up molecules, which make up cell organelles and structures. In multicellular organisms, similar cells form tissues.

Detailed explanation-5: -Schwann concluded three things that became vital components of the cell theory. First, Schwann concluded that both plants and animals were composed of cells. Second, these cells have independent lives. Third, these independent lives are subject to the organism’s life.