Answer:
The answer is unicellular
The olfactory epithelium is a specialized epithelial tissue inside the nasal cavity that is involved in smell. In humans, it lies on the roof of the nasal cavity about 7 cm above and behind the nostrils.
It’s iterative ontogenetic and di - or polymorphic
Answer:
it happens when 2 organisms jelp each other beneficial.
Explanation:
eg:algae and leguminous plants.the algae live on the roots and take in the nitrogen from the soil,which the plant cannot do and needs for growth.it takes in the nitrogen and pases it to the roots and even make the soil loose for the roots to move and they get a living space(algae on the roots).