Question

A basket of vegetables contains carrot, potato, radish and tomato. Which of them represent the correct homologous structures?
A)Carrot and potato
B)Carrot and tomato
C)Radish and carrot
D)Radish and potato

Answer 1

Hint: The homologous structures do not have to look precisely the same, or have the same function. The most important part, as observed by their name, is that they are structurally similar. They originated as a result of the adaptation to a different environment.

Complete answer:
Homologous structures are defined as those structures that have the same origin but can perform the same or different functions in different organisms. Homologous structures are usually inherited from a common ancestor as a result of divergent evolution. Some examples of homologous structure include the forelimbs of man and frogs apparently have the same basic design of bones but carry out different functions.

Now let us find solution from given options:
Carrot and potato : Carrot are modification of roots while potato is modification of stem so they are not homologous but they both store food so serve as analogous organs.
Carrot and tomato : Tomato is not a kind of modification and is not underground.
Radish and carrot : Carrot and radish are homologous structures because they are modifications of root for food storage. They contain different sets of nutrients and have different functions.
Radish and potato : Radish are modification of roots while potato is modification of stem so they are not homologous but they both store food so serve as analogous organs.

Hence, the correct answer is option (C)

Note: Rudimentary organs such as for instance the human tailbone, how much reduced from their functional state, are readily understood as signs of evolution, the explanation being that they were cut down by natural selection from functioning organs when their functions were no longer needed, but make no sense at all if species are considered to be fixed. The tailbone is a homologous organ to the tails of other primates.