Final answer:
The beginning of the cochlear partition is known as the basilar membrane, which is crucial for our hearing as it supports the organ of Corti and the mechanoreceptor hair cells activated by fluid dynamics.
Step-by-step explanation:
The start of the cochlear partition is called the basilar membrane. This membrane extends from the central core of the cochlea and plays a crucial role in our ability to hear. It is anchored by the organ of Corti, which contains the mechanoreceptor hair cells. These cells are activated by the movement of fluids within the cochlea, specifically within the scala vestibuli and scala tympani that flank the cochlear duct. As the fluid waves move through these chambers, they cause the basilar membrane to move, and this movement depends on the frequency of the waves. Higher frequency waves affect the region near the base of the cochlea, whereas lower frequency waves affect the region near the tip.