Which of the following is not a characteristic feature of sponges?

Options

A. Presence of ostia
B. Indirect development
C. Intracellular digestion
D. Cellular level of organization

Answer

To determine which of the following is not a characteristic feature of sponges, we need to analyze each option provided in the question. Here’s a step-by-step breakdown of the characteristics of sponges:

### Step 1: Understand the Characteristics of Sponges
Sponges, scientifically known as Porifera, are simple organisms with unique features. We need to evaluate the options given in the question against known characteristics of sponges.

### Step 2: Evaluate Each Option
1. **Presence of Ostia**: Sponges have numerous small pores called ostia that allow water to enter their bodies for feeding and respiration. This is a characteristic feature of sponges.

2. **Indirect Development**: Sponges undergo a form of indirect development, where they pass through a larval stage that is non-feeding. This is also a characteristic feature of sponges.

3. **Intracellular Digestion**: Sponges do not have a digestive system like more complex animals. Instead, they digest food at the cellular level, which is indeed a characteristic feature of sponges.

4. **Cellular Level of Organization**: Sponges exhibit a cellular level of organization, meaning they are composed of specialized cells but lack true tissues and organs. This is also a characteristic feature of sponges.

### Step 3: Conclusion
After evaluating all the options, we find that all the mentioned features (presence of ostia, indirect development, intracellular digestion, and cellular level of organization) are indeed characteristic features of sponges. Therefore, there is no option that is not a characteristic feature of sponges.

### Final Answer
None of the options provided is incorrect; all are characteristic features of sponges.

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