Cell is a unit of

Options

A. Structure
B. Function
C. Mass of protoplasm
D. All the above

Answer

To answer the question "Cell is a unit of:", we will analyze each option provided and determine the correct answer step by step.

### Step 1: Understanding the Definition of a Cell
A cell is the basic structural and functional unit of all living organisms. It is often referred to as the "building block of life."

**Hint:** Remember that cells are fundamental to both structure and function in living organisms.

### Step 2: Analyzing the Options
- **Option A: Structure** - Cells have a defined structure, including components like the plasma membrane, cytoplasm, and organelles. Therefore, cells are indeed a unit of structure.

- **Option B: Function** - Cells perform various functions necessary for life, such as metabolism, energy production, and reproduction. Thus, they are also a unit of function.

- **Option C: Mass of Protoplasm** - Protoplasm is the living substance within a cell, which includes the cytoplasm and the nucleus. Cells contain protoplasm, making them a unit of mass of protoplasm.

### Step 3: Conclusion
Since cells are units of structure, function, and mass of protoplasm, we can conclude that the correct answer is:

**Option D: All of the above.**

### Final Answer
The answer to the question "Cell is a unit of" is **D: All of the above.**

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