The simplest type of canal system in porifera is

Options

A. Sycon type
B. Ascon type
C. Radial type
D. Leucon type

Answer

To determine the simplest type of canal system in Porifera, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Types of Canal Systems in Porifera**:
- Porifera, or sponges, have different types of canal systems that facilitate water flow and nutrient absorption. The main types are Ascon, Sycon, Leucon, and Radial.

2. **Identify the Characteristics of Each Type**:
- **Ascon Type**: This is the simplest form. Water enters through small pores (ostia) into a central cavity called the spongocoel and exits through a larger opening called the osculum.
- **Sycon Type**: This is a more advanced type where the body wall is folded, allowing for more surface area and more pores.
- **Leucon Type**: This is the most complex type, characterized by a branched canal system with many small chambers.
- **Radial Type**: This is not commonly referred to in the context of Porifera canal systems.

3. **Evaluate the Options**:
- Given the descriptions:
- **Sycon type**: Advanced, not the simplest.
- **Ascon type**: Simplest, as it has a straightforward structure.
- **Radial type**: Not applicable in this context.
- **Leucon type**: Complex, not the simplest.

4. **Conclude the Answer**:
- Based on the characteristics and complexity of the canal systems, the simplest type of canal system in Porifera is the **Ascon type**.

### Final Answer:
The simplest type of canal system in Porifera is **Ascon type**.

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