Question

Dental formula of elephant is
A. \(\dfrac{{1,\,0,\,0,\,3}}{{0,\,0,\,0,\,3}}\)
B. \(\dfrac{{1,\,0,\,0,\,3}}{{1,\,0,\,0,\,3}}\)
C. \(\dfrac{{1,\,0,\,2,\,3}}{{1,\,0,\,1,\,3}}\)
D. \(\dfrac{{2,\,0,\,3,\,3}}{{1,\,0,\,3,\,3}}\)

Answer 1

Hint: Elephants have two incisors which are adapted as tusks in the upper jaw. As the dental formula is for one side of the jaw, the total number of teeth in the dental formula is multiplied by 2.


Complete answer:
Mammals have teeth in varying sizes and types, which is known as heterodontia, which allows different teeth to be specialised for various roles. These specialised teeth include: incisors (I), canine teeth (C), premolar teeth (P) and molar teeth (M). Most mammals usually have two types of teeth: a set of deciduous teeth (milk teeth) and a permanent set.
Dental formula is a way of defining the number and arrangement of teeth in humans and animals by using letters and figures. It is described as an expression of the number of each type of tooth on one side of the upper jaw over the number of teeth on one side of the lower jaw. The letter refers to the type of teeth (I = incisor, C = canine, P = premolar, M = molar). The dental formulae for various species vary by diet and function. Since the two sides of each jaw have the same number and type of teeth, the number of teeth on one side alone is generally reflected in the formula.
The dental formula for elephant is
Deciduous (Milk teeth): I =1/0, C=0/0, PM = 0/0, M = 3/3; Total = \(7 \times 2 = 14\)
Adult: I =1/0, C= 0/0, PM= 3/3, M= 3/3; Total= \(13 \times 2 = 26\)

Thus, the correct answer is option A i.e.,\(\dfrac{{1,\,0,\,0,\,3}}{{0,\,0,\,0,\,3}}\)

Note:The chewing teeth of the elephant are removed six times in its lifetime. New teeth do not grow from the jaw like the other mammals. Instead, fresh teeth grow from the back of the mouth and move in to drive out the existing ones.