Wisconsin Esthetics State Board Practice Test

What is the basic unit of life composed of protoplasm?

1. Tissue

2. Organ

3. Cell

4. System

The correct answer is: Cell

The correct answer is a cell, as it is indeed recognized as the basic unit of life. Cells are the smallest structural and functional units capable of independent existence and life processes. They contain protoplasm, which encompasses the living material within the cell, including the cytoplasm and the nucleus. This protoplasmic content is where cellular activities, such as metabolism and reproduction, occur. In biology, tissues are composed of groups of similar cells that work together to perform specific functions. While tissues are essential for the function of organs, they are not the fundamental unit of life. Similarly, organs are made up of different types of tissues working in harmony to carry out complex functions within an organism. Organ systems consist of groups of organs that perform interrelated functions, illustrating a higher level of biological organization beyond individual cells. Therefore, while tissue, organ, and system play critical roles in the structure and function of living organisms, none of them serve as the fundamental unit of life like the cell does.