Point out the mammalian characters

Options

A. Diaphragm, four-chambered heart , lungs
B. Hairy skin, viviparity, feathers
C. Fins, gills, viviparity
D. Neural gland, gills, four-chambered heart

Answer

**Step-by-Step Solution:**

1. **Definition of Mammals**: Begin by understanding that mammals are a class of animals characterized by specific traits that distinguish them from other animal classes.

2. **Key Mammalian Characteristics**:
- **Mammary Glands**: Mammals possess mammary glands that produce milk for feeding their young, which is a defining feature of this class.
- **Hair or Fur**: All mammals have hair or fur on their skin, which provides insulation and helps in temperature regulation.
- **Sweat Glands**: These are present on the skin and help in thermoregulation through the process of sweating.
- **Lungs with Alveoli**: Mammals have lungs that contain alveoli, which are tiny air sacs where gas exchange occurs.
- **Four-Chambered Heart**: Mammals have a four-chambered heart consisting of two atria and two ventricles, allowing for efficient circulation of blood.
- **Diaphragm**: This muscle is located below the lungs and plays a crucial role in respiration by helping to expand and contract the chest cavity.
- **Neocortex**: This part of the brain is involved in higher-order brain functions such as sensory perception, cognition, and motor commands.

3. **Comparison of Options**:
- **Option 1**: Diaphragm, 4-chambered heart, and lungs - This option includes valid mammalian characteristics.
- **Option 2**: Hairy skin, viviparity, and feathers - While hairy skin is correct, feathers are not present in mammals, making this option incorrect.
- **Option 3**: Fins, gills, and viviparity - Fins and gills are not characteristics of mammals, so this option is incorrect.
- **Option 4**: Neural glands, gills, and a four-chambered heart - While the four-chambered heart is correct, gills are absent in mammals, making this option incorrect.

4. **Final Answer**: The mammalian characters include diaphragm, four-chambered heart, and lungs.

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