Question

Read the passage and answer the following questions.

The following data table shows the number of different amino acids in the beta hemoglobin chain of various organisms compared to the human beta chain.

Organism	Number of different amino acids
Human	0
Mouse	27
Frog	68
Monkey	11
Lamprey	125
Chicken	35
Gibbon	2

Human haemoglobin and Gibbon haemoglobin are even more closely related than another organism in the table and yet humans and gorilla are considered as different species because

• A. Their hemoglobin chains differ by a single amino acid
• B. Human hemoglobin and gorilla hemoglobin have different functions
• C. They are unable to interbreed
• D. They are the result of convergent evolution
• E. They are the result of parallel evolution

Answer 1

Answer: (C)

They are unable to interbreed

Species is group of individuals that can potentially interbreed to produce fertile offspring. Main criteria of putting two individuals under same species is their ability to interbreed to produce fertile offspring, no difference in structure or function of a protein; gibbons and human can not interbreed and are kept under different species. Gibbons and human share common ancestor and are result of divergent evolution.

Therefore, the correct answer is option C.