List two peculiar features of open circulatory system.

Explanation

### Step-by-Step Text Solution:

1. **Definition of Open Circulatory System**: An open circulatory system is a type of circulatory system commonly found in invertebrates, where the blood is not confined to vessels but flows freely through cavities in the body.

2. **Peculiar Feature 1 - Blood Flow**: One of the peculiar features of an open circulatory system is that the blood flows at low pressure and low speed. This is because there are no blood vessels to maintain high pressure, resulting in a slower movement of blood.

3. **Peculiar Feature 2 - Direct Contact**: Another peculiar feature is that there is direct contact between the blood and body cells. This allows for efficient exchange of materials (such as nutrients and waste) between the blood and the cells, as the blood bathes the tissues directly.

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