Mammalian teeth are

Options

A. Acrodont
B. Homodont
C. Thecodont
D. Polyphyodont

Answer

**Step-by-Step Solution:**

1. **Understanding Mammalian Teeth**: Mammalian teeth are characterized by their heterodont nature, meaning they consist of different types of teeth that serve various functions.

2. **Types of Teeth in Mammals**: In one quadrant of the jaw (either upper or lower), mammals typically have:
- 2 Incisors (1 central incisor and 1 lateral incisor)
- 1 Canine
- 2 Premolars
- 3 Molars (with the third molar often referred to as the wisdom tooth)

3. **Morphology and Structure**: Each type of tooth has a distinct morphology and external structure, allowing easy identification of incisors, canines, premolars, and molars.

4. **Classification of Teeth**:
- **Thecodont**: This term refers to teeth that are embedded in the sockets of the jaw bones (alveolar bones). This is a characteristic of mammalian teeth.
- **Homodont**: This term refers to organisms that have teeth of the same type, which is not applicable to mammals.
- **Polyphyodont**: This refers to organisms that continuously replace their teeth throughout their life, which is not the case for humans.
- **Monophyodont**: This refers to having only one set of teeth in a lifetime, which is seen in some lower organisms.

5. **Diphyodont Teeth**: Humans specifically have diphyodont teeth, meaning they develop two sets of teeth during their lifetime:
- Deciduous teeth (temporary)
- Permanent teeth (which replace the deciduous teeth around the age of 12).

6. **Conclusion**: Based on the classification and characteristics discussed, the correct answer to the question is that mammalian teeth are **thecodont**.

**Final Answer**: The correct option is **3. Thecodont**.

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