Which of the following statements are correct about the cell theory of Schleiden and Schwann?

(a) All living things are composed of one or more cells.

(b) New cells are formed from the pre-existing cells.

(c) There are basic similarities in chemical composition and metabolic functions of cells.

(d) The activity of an organism is collective activities and interactions of its cellular structures.

The correct answer is All of the above.

Key Points

• The cell theory proposed by Schleiden and Schwann states the following:
  • All living things are composed of one or more cells.
  • New cells arise from pre-existing cells.
  • Cells have basic similarities in their chemical composition and metabolic functions.
  • The activities of an organism are the result of the collective activities and interactions of its cells.
• Each of the statements (a), (b), (c), and (d) aligns with the principles of this theory.

Additional Information

• The addition of the idea that cells arise from pre-existing cells was contributed by Rudolf Virchow, further refining the cell theory.
• The cell theory is a fundamental concept in biology and applies universally to all living organisms.