Assertion: Adrenal cortex is not vital for survival and may be removed without subsequently leading to death.
Reason: Adreanl cortex secretes a number of steroid hormones which have only cumulative effects on the hormones of other glands.

Explanation

To analyze the assertion and reason provided in the question, we can break down the information step by step.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that the adrenal cortex is not vital for survival and can be removed without leading to death.
- **Evaluation**: This is incorrect. The adrenal cortex plays a crucial role in producing essential hormones that regulate various bodily functions. Its removal can lead to severe health issues and can be fatal.

2. **Understanding the Reason**:
- The reason claims that the adrenal cortex secretes a number of steroid hormones which have only cumulative effects on the hormones of other glands.
- **Evaluation**: This statement is also incorrect. The hormones produced by the adrenal cortex, including glucocorticoids, mineralocorticoids, and sex hormones, have significant and direct effects on metabolism, water balance, and sexual characteristics, respectively. They do not merely have cumulative effects; they are vital for maintaining homeostasis and overall health.

3. **Conclusion**:
- Since both the assertion and the reason are incorrect, the correct answer to the question is that both the assertion and the reason are false.

### Final Answer:
Both Assertion and Reason are incorrect.

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