Amensalism can be represented as : (NEET Exam 2021- Biology Section)

(1) Species A (−) ; Species B (0) 

(2) Species A (+) ; Species B (+) 

(3) Species A (−) ; Species B (−) 

(4) Species A (+) ; Species B (0)

Solution: 1

Types of symbiotic relationships:

1. Mutualism- Both species benefit i.e. Species A (+); Species B (+)

2. Commensalism- In which one species benefits and the other remains unaffected i.e. Species A (+); Species B (0)

3. Parasitism- One species benefits from the relationship at the expense of the other i.e. Species A (+); Species B (-)

4. Amensalism- One species is harmed or killed by the other and one is unaffected by the other i.e. Species A (-); Species B (0)

Hence, option (1) is correct.