The cell is a functional unit of living organisms because

This Biology question is asking why the cell is considered the functional unit of living organisms. The options are: A) multicellular organisms are made up of cells, B) all cells in a multicellular organism function as a single cell, C) the function of a multicellular organism is the sum total of the functions of its constituent cells, D) the function of a single cell is superior to that of the multicellular organism, and E) the cells of a multicellular organism are similar in structure.

The correct option is A, which states that multicellular organisms are made up of cells. This means that every living organism, no matter how complex, is composed of one or more cells. Cells are the basic unit of life, and they carry out all the necessary functions required for an organism to live. For example, cells are responsible for obtaining and processing energy, responding to stimuli, and reproducing.

Option B is incorrect because cells in multicellular organisms do not function as a single cell. Instead, they work together in a coordinated manner to carry out specific functions.

Option C is partially correct in that the function of a multicellular organism is the sum total of the functions of its constituent cells. However, it is important to note that the interactions between cells and the way they communicate with each other are also critical for the proper function of a multicellular organism.

Option D is incorrect because the function of a multicellular organism is not inferior to that of a single cell. In fact, the complexity and diversity of multicellular organisms are due to the specialization and differentiation of their cells.

Option E is also incorrect because although cells in a multicellular organism may have similar structures, they can have vastly different functions and roles within the organism.

In summary, the cell is considered the functional unit of living organisms because every living organism is composed of one or more cells, and cells carry out all the necessary functions required for an organism to live.