How do chemicals made by organisms help establish and maintain a uniform distribution pattern?

Which of the following is the main purpose of a human community?

The fauces connects which of th following structures to the oropharynx

Where is the nictitating membrane found? a. between the eyelid and the eyeball b. between the retina and the optic nerve c. between the outer and middle ear d. in the organ of corti in the middle ear