The Senses Hearing external/middle ear
The senses - Sound, noise, hearing all can be traced back to the ear in which a mechanoreceptor turns sound waves into electrical impulse that in turn are sent to the brain to be perceived. The mechanoreceptors of the ear involved hearing and equilibrium send impulses to the brain for interpretation. The ear is broken down into three main sections the external ear, middle ear, and Inner ear.
The external ear is made up of two parts the auricula or pinna, and the external acoustic meatus. The former projects from the side of the head and serves to collect the vibrations of the air by which sound is produced; the latter leads inward from the bottom of the auricula and conducts the vibrations to the tympanic cavity. The tympanic membrane is the medical term for the eardrum.
From the middle ear glands that produce a eaxy substance are the ceruminus glands. The medical term for ear wax is cerumen which is produced by the ear. The ear is a very sensitive instrument of the human body it can very easily be impaired by soundwaves, scar tissue, Viruses, Damage to the ear drum and the excess of cerumen in the ear cannel. The bones in the middle ear that cover sound waves into electrical impulses are the ossicles, malleus, and stapes. The “hammer” in the middle ear is also called the malleus it got its name because of the shape of the bone. The “incus” has received its name from its supposed resemblance to an anvil, but it is more like a premolar tooth, with two roots, which differ in length, and are widely separated from each other. Finally, the “stirrup” bone of the middle ear got its name because of the shape which resembled a saddle stirrup.
The Eustachian tube is a membrane lined tube that connects the middle ear space to the back of the nose. Its primary function is to ventilate the middle ear, ensuring that the pressure inside the ear remains at near normal ambient air pressure. The secondary function of the Eustachian tube is to drain any accumulated secretions, infection, or debris from the middle ear space. Several small muscles located in the back of the throat and palate control the opening and closing of the tube.
