JAMB - Biology (2005 - No. 30)
A function of the part labelled II is to
equalize pressure on both sides of the tympanum
conduct sound waves to the brain
help the animal maintain balance or posture
transform sound waves into electric impulses
Forklaring
The part labelled II is the eustachian tube and it's function is to balance or equalize air pressure between the middle ear and the outside environment, ventilate the middle ear, and protect it from nasopharyngeal secretions and sound pressures.