The term used to describe the two types of cell that looks different due to specific function they perform are called as differentiated cells.
Explanation:
Differentiated cells are those cells that have divided to perform specific function in an organism. Such cells unite to form a tissue. However, the stem cells possess the ability into different cell types to perform different functions. Some cells lose the ability to divide further.
Example - nerve cell. Plants are multicellular and thus has different types of cells to perform different functions. If such cells are visualized under the microscope, then they appear different in structure because of their difference in function.