Question

What is the digital formula for the hind limbs of frogs?
a) 0,2,2,3,3
b) 2,2,3,3,3
c) 2,2,3,4,3
d) 0,2,1,2,3

Answer 1

Hint:Digital formula is a way to represent phalanges in animals. Phalanges is just the number of bones present in each finger or finger like structure present in different animals in their limbs and forelimbs.

Complete answer:
 It is a series of different numbers in which the count of digits will tell us the number of fingers present in one limb or forelimbs and each digit will tell us how many bones are present in that particular finger.
Example Humans have 2,3,3,3,3 digital formula for both hands and feet, this means Humans have 2 bones in thumb, 3 bones in every finger and Humans have 4 fingers. Thus, we write 3,3,3,3.
This digital formula makes it very easy to remember the functioning of bones of different animals. And also help in bone anatomy a lot. Functioning of limbs and forelimbs can be easily found out from this formula.
In the given option A, 0,2,2,3,3 – This represents zero bones in 1st hind limb have no bones which is not the case. In frog It has 2 bones in the 1st hind limb. So, this option is not correct.
In option B, 2,2,3,3,3- This represents 2 bones in the 1st hind limb which is correct. 2 bones in 2nd hind limb, which is also true for frog. 3 bones in 3rd hind limb, which is also correct. Now, for the 4th hind limb it tells us that there exist 3 bones which is not correct. In the frog's hind limb, the 4th finger has four bones. Thus, this option is also not correct.
In option C, 2,2,3,4,3- this represents 2 bones in the 1st hind limb which is correct. 2 bones in 2nd hind limb, which is also true for frog. 3 bones in 3rd hind limb, which is also correct. And 4 bones in 4th hind limb and 3 bones in 5th hind limb. Thus, this option correctly represents the digital formula of frog’s hind limb.

  So, the correct option is option C.

Note: Please carefully check the sequence because we during exam, due to exam pressure misunderstood the digits and tick incorrect option which is given to confuse us. The digital formula of Humans and frogs is very important. It has already been asked in many exams.