Q. $Nicotiana\ sylvestris$ flowers only during long days while N. tobacum flowers only during short days. If raised in the laboratory under different photoperiods, they can be induced to flower at the same time and can be cross fertilized to produce self-fertile offspring. What is the best reason for considering N. sylvestris and N.tobacum to be separate species?
A) They are physiologically distinct
B) They are morphologically distinct
C) They cannot interbreed in nature
D) They are reproductively distinct
Explanation
Biological concept of species says that only the members of a species can breed freely in nature to produce fertile offsprings. The plant tobacco (Nicotiana) has two different species, Nicotiana tobaccum and Nicotiana sylvestris. These two species cannot reproduce freely.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.