Explain how sound waves in the environment lead to production of action potentials in the inner ear and how different sound frequencies are detected and distinguished in terrestrial vertebrates.

Explanation:

Hearing is one of the developed feature in terrestrial vertebrates. Terrestrial vertebrates ears are able to detect and hear the broad range of sound frequencies.

The inner ear of vertebrates is responsible for two main functions including ability of hearing with the sensory hair cells and individual balancing. The inner ear in terrestrial vertebrates made up of membranous system which contains a fluid called endolymphatic fluid which is covered by bony labyrinth containing perilymphatic fluid.

The sound waves in envionment lead the mechanical displacment of hair cells present in the ampullae of the semicircular canals (SCs) of ear which is filled with endolymphatic fluid. The movement of fluid in inner air produces sensory signals and sent it to nerve cells for further action.

The hair cells further helps to detect and distinguish the sound frequencies by the displacment of hair cells in inner cells. for example if sound frequency falls in to ampullae of  semicircular canals it will help to detect rotational movement, while if the sound frequencies passes through hair cells and moves into  the otolithic layer of the maculae, it will help to detects longitudinal and vertical acceleration.