The following provides aeration for tissue growth "invitro"

Options

A. Macro and micronutrients
B. Amino acids and vitamins
C. Growth regulators
D. Non-absorbent cotton of culture vessels

Answer

**Step-by-Step Solution:**

1. **Understand the Concept of In Vitro:**
- In vitro refers to studying biological processes in a controlled environment outside of a living organism, typically in a test tube or culture flask.

2. **Identify the Components of the Culture Flask:**
- A culture flask contains a growth medium and the tissue that is being studied or grown.

3. **Recognize the Needs of the Tissue:**
- The tissue requires oxygen, nutrients, and water to grow. These must be provided externally since the tissue is not in its natural environment.

4. **Evaluate the Options Given:**
- The options provided are:
- A) Macro and micronutrients
- B) Amino acids and vitamins
- C) Growth regulators
- D) Non-absorbent cotton of the culture vessel

5. **Analyze Each Option:**
- **Macro and Micronutrients:** These are essential for tissue growth but do not specifically provide aeration.
- **Amino Acids and Vitamins:** These are important for growth but again do not provide aeration.
- **Growth Regulators:** These substances help in cell enlargement and growth but are not responsible for aeration.
- **Non-absorbent Cotton of the Culture Vessel:** This component is critical as it allows for aeration while preventing contamination. It does not absorb the medium, ensuring that oxygen can reach the tissue.

6. **Conclusion:**
- The correct answer is **D) Non-absorbent cotton of the culture vessel** as it provides aeration necessary for tissue growth in vitro.

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