Question

An example of homologous organs is
(a) Our arm and a dog’s fore-leg
(b) Our teeth and an elephant’s tusks
(c) Potato and runners of grass
(d) All of the above.

Answer 1

Hint: When we have a similar structure and have similar evolutionary relations these types of organs are homologous in nature.

Complete step by step answer:
Homologous structures are structures that are derived from a common ancestor. Even if they are superficially different, they are developmentally related. Homologous structures do not share the same function. Example: The hoping legs of the frog contain the same bones as our arm, but the frog’s legs are highly modified to perform a different function (hoping). Our teeth and an elephant’s tusks have the same structure, but their functions are different. We chew with our teeth, whereas elephants use their tusks to hold things. The Tuber of Potato and runners of grass are also homologous because they both represent a stem.

So, the correct answer is ‘(d) All of the above’.

Additional Information:
There is wide evidence that supports evolution. Two of them are homologous and analogous structures. The difference between them is as follows:

Homologous Structure	Analogous Structure
Similar anatomy	Dissimilar anatomy
Dissimilar functions	Similar Functions
Inherited from a common ancestor	Not inherited from ancestors
Develops in related species	Develops in unrelated species
A result of divergent evolution	A result of convergent evolution
These developed as a result of the adaptation to a different environment	These developed as a result of the adaptation to a similar environment

Note: The observations of structural homology support the causal hypothesis of evolutionary homology: that the common structural organization results from common ancestry. The evidence of analogous structures further supports the evolutionary homology concept.