Which class of animals possess two chambered heart?

Options

A. Pisces
B. Amphibians
C. Reptiles
D. Both (a) and (b)

Answer

To determine which class of animals possesses a two-chambered heart, we can follow these steps:

### Step 1: Understand the Structure of Hearts in Different Animal Classes
- Animals have different types of hearts based on their evolutionary adaptations and classifications. The heart structure can vary from two chambers to three or four chambers.

### Step 2: Identify the Classes of Animals
- The main classes of animals include:
- **Pisces (Fish)**
- **Amphibia (Amphibians)**
- **Reptilia (Reptiles)**
- **Aves (Birds)**
- **Mammalia (Mammals)**

### Step 3: Analyze the Heart Structure in Each Class
- **Pisces (Fish)**: Fish typically have a two-chambered heart, consisting of one atrium and one ventricle.
- **Amphibia (Amphibians)**: Amphibians usually have a three-chambered heart, with two atria and one ventricle.
- **Reptilia (Reptiles)**: Most reptiles also have a three-chambered heart, though some have a partially divided ventricle.
- **Aves (Birds)**: Birds possess a four-chambered heart.
- **Mammalia (Mammals)**: Mammals also have a four-chambered heart.

### Step 4: Conclusion
- Based on the analysis, the class of animals that possesses a two-chambered heart is **Pisces (Fish)**.

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