Which of the statements are correct?
I.Occurence of different types of tissues ,organs and organ system results in division of labour
II.A new cell always develops by the division of a pre existing cells
III.Cells are totipotent
IV.Cell is the smallest unit,capable of independent existence and performing the essential functions of life.
The correct option is

Options

A. I,II,III
B. I,III,IV
C. II,III,IV
D. all of the above

Answer

To determine which statements are correct regarding cells and their functions, let's analyze each statement step by step.

### Step-by-Step Solution:

1. **Statement I: Occurrence of different types of tissues, organs, and organ systems results in division of labor.**
- This statement is correct. In multicellular organisms, different types of tissues (like muscular, nervous, connective, etc.) form organs (like heart, lungs, liver) that work together in organ systems (like circulatory, respiratory, digestive). This specialization allows for efficient functioning, known as division of labor.

2. **Statement II: A new cell always develops by the division of a pre-existing cell.**
- This statement is also correct. The principle of cell theory states that all cells arise from pre-existing cells through processes such as mitosis (for somatic cells) and meiosis (for germ cells). Thus, new cells are formed only from existing cells.

3. **Statement III: Cells are totipotent.**
- This statement is partially correct but requires clarification. While totipotency refers to the ability of a single cell (like a zygote) to develop into a complete organism, not all cells are totipotent. Only the zygote and some early embryonic cells have this capability. Therefore, this statement is misleading as it implies that all cells possess this ability.

4. **Statement IV: Cell is the smallest unit capable of independent existence and performing the essential functions of life.**
- This statement is correct. Cells are indeed the smallest units of life that can exist independently (like prokaryotic cells such as bacteria) and perform essential life functions (like metabolism, growth, and reproduction).

### Conclusion:
Based on the analysis:
- **Correct Statements:** I, II, and IV.
- **Incorrect Statement:** III (not all cells are totipotent).

Thus, the correct option is that statements I, II, and IV are correct.

### Final Answer:
The correct option is: **I, II, and IV are correct.**

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