Final answer:
The cochlea is an inner ear structure crucial for hearing, as it transduces sound vibrations into electrical signals for the brain.
Step-by-step explanation:
Both statements A and B about the cochlea are true. The cochlea is a structure of the inner ear and plays a crucial role in the process of hearing. It is responsible for the transduction of sound, which means it transforms vibrations from sound waves into electrical signals that can be interpreted by the brain. This process begins when sound waves enter the ear and are directed through the outer ear to the tympanic membrane (eardrum), which vibrates.
These vibrations are then transmitted by the ossicles, three tiny bones in the middle ear, to the oval window of the cochlea. Inside the cochlea, fluid is set in motion, creating pressure waves that move the basilar membrane and stimulate hair cells in the organ of Corti. These hair cells convert the mechanical movements into electrochemical signals that are sent to the brain via the auditory nerve, allowing us to perceive sound.