Which of the following statements is not true?

Options

A. Life span is the period from birth to the natural death of an organism
B. All small organisms have very short life span
C. Life expectancy is the characteristic of populations
D. Maximum life span is the characteristic of species

Answer

To determine which statement is not true, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understand the Concept of Lifespan**:
- Lifespan is defined as the period from birth to the natural death of an organism. This definition is universally accepted in biology.

2. **Evaluate the First Statement**:
- The first statement claims that "Lifespan is the period from birth to the natural death of an organism."
- This statement is true as it aligns with the definition of lifespan.

3. **Evaluate the Second Statement**:
- The second statement asserts that "All small organisms have very short life."
- This statement is not true because not all small organisms have short lifespans. For example, certain small animals like tortoises can live for many years, while others may have shorter lifespans. Thus, this statement is incorrect.

4. **Evaluate the Third Statement**:
- The third statement says, "Life expectancy is the characteristic of populations."
- This statement is true. Life expectancy refers to the average period that a population is expected to live, which is indeed a characteristic of populations.

5. **Evaluate the Fourth Statement**:
- The fourth statement claims that "The maximum lifespan is the characteristic of species."
- This statement is also true. Different species have different maximum lifespans, which can be used to characterize them.

6. **Conclusion**:
- After evaluating all the statements, the second statement is the only one that is not true. Therefore, the correct answer to the question is the second statement.

### Final Answer:
The statement that is not true is: "All small organisms have very short life."

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