Closed circulatory system occurs in

Options

A. Snail
B. Cockroach
C. Cuttle fish
D. All of these

Answer

To answer the question "Closed circulatory system occurs in," we need to analyze the options provided: snail, cockroach, cuttlefish, or all of these. Here’s a step-by-step solution:

### Step 1: Understand the Types of Circulatory Systems
- There are two main types of circulatory systems: **closed** and **open**.
- In a **closed circulatory system**, blood is contained within blood vessels and is pumped by the heart.
- In an **open circulatory system**, blood (hemolymph) is not confined to blood vessels and bathes the organs directly.

### Step 2: Identify the Organisms
- **Snail**: Belongs to the phylum Mollusca. Generally, mollusks have an open circulatory system, but there are exceptions.
- **Cockroach**: Belongs to the phylum Arthropoda. Arthropods typically have an open circulatory system.
- **Cuttlefish**: Also belongs to the phylum Mollusca. However, cuttlefish (and other cephalopods like octopus and squid) have a closed circulatory system.

### Step 3: Analyze Each Option
- **Snail**: Open circulatory system.
- **Cockroach**: Open circulatory system.
- **Cuttlefish**: Closed circulatory system (exception among mollusks).

### Step 4: Conclusion
Among the options provided, the organism that has a closed circulatory system is the **cuttlefish**. Therefore, the correct answer is **cuttlefish**.

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