Which physiologist stated all animals are made of cells?

Which physiologist stated all animals are made of cells?

• A. Theodore Schwann
• B. Matthias Schleiden
• C. Robert Hooke
• D. Anton van Leeuwenhoek

Answer: (A)

Cell theory says that living matter is built from cells, the basic units of life. Theodor Schwann extended this idea to animals, showing that animal tissues are composed of cells just as plant tissues are. This unified view—that both plants and animals are made of cells—forms the foundation of the statement that all animals are made of cells. Schleiden had already argued that plants are made of cells, which complemented Schwann’s animal work. Hooke coined the term “cell” from his cork observations but didn’t establish the animal side of the theory, and van Leeuwenhoek described microorganisms without articulating the cellular basis of animal life.

Cell theory says that living matter is built from cells, the basic units of life. Theodor Schwann extended this idea to animals, showing that animal tissues are composed of cells just as plant tissues are. This unified view—that both plants and animals are made of cells—forms the foundation of the statement that all animals are made of cells. Schleiden had already argued that plants are made of cells, which complemented Schwann’s animal work. Hooke coined the term “cell” from his cork observations but didn’t establish the animal side of the theory, and van Leeuwenhoek described microorganisms without articulating the cellular basis of animal life.