Dental formula in human beings is

Options

A. `(2,1,2,3)/(2,1,2,3)`
B. `(2,1,2,3)/(2,1,2,2)`
C. `(2,1,2,3)/(2,1,2,4)`
D. `(2,1,3,2)/(2,1,3,2)`

Answer

**Step-by-Step Solution:**

1. **Understanding Dental Formula**: The dental formula is a way to represent the number and types of teeth in an organism. It shows the arrangement of teeth in each half of the upper and lower jaws.

2. **Types of Teeth in Humans**: Humans have four types of teeth:
- Incisors
- Canines
- Premolars
- Molars

3. **Counting the Teeth**: For adult humans, the typical number of each type of tooth is:
- Incisors: 2
- Canines: 1
- Premolars: 2
- Molars: 3

4. **Writing the Dental Formula**: The dental formula for adults can be expressed as:
- Upper jaw: 2 incisors, 1 canine, 2 premolars, 3 molars
- Lower jaw: 2 incisors, 1 canine, 2 premolars, 3 molars
- This can be written as:
\[ \text{Dental Formula} = \frac{2 \, 1 \, 2 \, 3}{2 \, 1 \, 2 \, 3} \]

5. **Calculating Total Number of Teeth**: Each half of the jaw has 8 teeth (4 from the upper jaw and 4 from the lower jaw). Therefore, the total number of teeth in an adult human is:
- \(8 \, \text{(upper jaw)} + 8 \, \text{(lower jaw)} = 16\)
- Since this is for each half, we multiply by 2 to get the total number of teeth:
- \(16 \times 2 = 32\)

6. **Conclusion**: The dental formula for adult human beings is:
\[ \frac{2 \, 1 \, 2 \, 3}{2 \, 1 \, 2 \, 3} \]
This matches with the first option provided in the question.

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