Which statement is a cornerstone of modern cell theory?

Which statement is a cornerstone of modern cell theory?

• A. Cells are the basic structural, functional units of life
• B. Metabolism occurs outside cells
• C. Genetic information is stored and passed via RNA
• D. Organisms are not composed of cells

Answer: (A)

The main idea here is that cells are the basic structural and functional units of life. This is the essential point of cell theory: the organization of life hinges on cells, with all structures and bodily functions arising from cellular activity. Metabolic processes, growth, and responses to the environment are carried out by cells, making them the smallest units capable of performing the activities necessary for life. The other statements don’t fit because metabolism is carried out inside cells, genetic information is stored in DNA (with RNA playing a role in transfer and expression but not as the primary storage), and organisms are indeed composed of cells.

The main idea here is that cells are the basic structural and functional units of life. This is the essential point of cell theory: the organization of life hinges on cells, with all structures and bodily functions arising from cellular activity. Metabolic processes, growth, and responses to the environment are carried out by cells, making them the smallest units capable of performing the activities necessary for life. The other statements don’t fit because metabolism is carried out inside cells, genetic information is stored in DNA (with RNA playing a role in transfer and expression but not as the primary storage), and organisms are indeed composed of cells.