External Structures

When a person with normal hearing hears the sound travels along the ear then bounces against the ear drum. The eardrum, the bones inside, and the cochlea vibrate and move thousands of tiny hairs inside the ear. When these hairs move an electrical response occurs. This electrical response goes to the hearing nerve and then it is send to the brain.

Basically how sound travels through the ear is a process of many steps. The sound waves are gathered by the pinna and then funneled into the meatus. Those waves then begin to vibrate the tympanic membrane which in turn hits against the malleus. The ossicle bones then vibrate like a chain reaction. The footplate will hit the oval window which triggers the fluid in the cochlea to move. The movement sways across the different hair cells creating impulses that are sent to the brain through the eighth cranial nerve.

The physiology of hearing starts with a vibration that occurs in the air which sends an acoustic signal to the ear drum. The signal is transduced into a mechanical signal that transmits through the inner ear and the cochlear nerve. Finally, the signal is

The middle ear has three ossicles (tiny bones) the hammer, the anvil, and the stirrup that connect the middle ear to the inner ear. When sound enters your middle ear, it causes the ossicles to vibrate. These vibrations then move into the cochlea, which is filled with fluid. When the vibrations move the fluid that is in the cochlea, it stimulates tiny hair cells that respond to different frequencies of sound. After the tiny hair cells are stimulated, they direct the frequencies of sound into the auditory nerve, as nerve impulses. (ASHA 2013)

“Auditory Processing Disorder is a measurable neurological defect located in the higher auditory neural pathways. Sound waves enter each ear canal and are passed through the middle ear where they are “prepared” for delivery to the cochlea (part of the inner ear). The cochlea “transduces” the sound waves into electric nerve pulses, which are sent to the brain by way of the hearing nerve (VIII Cranial nerve). The eighth nerve inserts at the brainstem, where a complex network

Two associated systems with the eye are the nervous and muscular systems. The eye is a part of the nervous system because it is responsible for sending, receiving, and processing information sent through the nerve impulses. The optic nerve is a part of the eye and part of the central nervous system. As humans, we see something through our eyes and react to it. If we see someone is going to hit us, we flinch. If we are reading something, or seeing a picture, we see it and process it. By seeing the world through our eyes, it allows us to react and process our surroundings. The eyes are also associated with the muscular system; it has a special system of muscles that allow the eyes to move. Movements of the ciliary muscles

The purpose for this experiment was to measure the reaction time for auditory stimuli using a measuring ruler and compare to visual cue. In auditory pathway, once the auditory signals arrive into inner ear, the Cochlear hair cells which is he auditory receptor cells, in the organ of Corti of the inner ear receive the sensory stimuli (Hudspeth 2014). There are two types of cochlear hair cells: the inner hair cell that carry out transmitting the signal to the rest of the auditory pathway, and outer cells that mediate the transmitting of information (Hudspeth 2014). According to (Tong, 2013), the cochlear hair cells or presynaptic neurons synapse with spiral ganglion, which are the first afferent nerve fibers. The basolateral membrane of the

The vestibular and cochlear portions of the vestibulocochlear nerve are functionally discrete, and so originate from different nuclei in the brain:

The semi-circular canal is connected to the cochlea. It is filled with fluid and is also known as the organ which keeps everything in balance (Roberts and Roberts, 2010). The main purpose of the semi-circular canal is that it senses movement and keep a balance in the head (Wright, 2007).

Biology relates to the human eye because if we didn't have certain organs or cells we would be able to see.There is three types of cells found in the human eye that allows us to see what's going. The first cell is called the Cone cell this plays a big part when were visualizing something.This cell is located in the retina and their role in the human eye is for colour vision and in relativity bright.The Cone cells also help us see colour for example red , green and blue also cones cells are less sensitive to light the also are able to add small details to the image and more faster changes to the image.

The ear is made up of an outer (external), middle and inner ear. The outer and middle ear is mainly involved in transmitting sounds to the inner ear where that sound is processed. The first step in this process involves sound waves entering the external auditory canal and passing the tympanic membrane (otherwise known as the eardrum- this separates the outer ear from the middle ear)( Vander A, Sherman J, Luciano D, 2001). As small air molecules (sound) passes through the tympanic membrane they cause it to vibrate and these vibrations are then passed onto the middle ear (Moore KL, Agur MRA, 2002). The middle ear formed from 3 tiny bones (malleus, incus and stapes)- known as auditory ossicles then

The mammalian cochlea is located within the inner ear and is responsible for the transduction of auditory stimuli from an organism’s external environment to the brain. The neurons that mediate this signal transduction are spiral ganglion neurons (SGN), a bipolar cell type with peripheral axons extending to mechanically sensitive hair cells (HC) in the organ of Corti (OC) and central axons that bifurcate and project to the dorsal and ventral cochlear nuclei (DCN, VCN) (Coate, et al., 2013). SGNs are divided into two classes determined by the hair cells to which they project: 90-95% of SGNs innervate inner hair cells (IHCs), whereas the remaining 5-10%

The relationship between the mass of the ossicles and tympanic plate area in the remingtonocetid and protocetid is comparable to the ear anatomy found in modern whales. The odontocete transmits sound by means of a large mandibular fat pad and received by the tympanic plate. Sound passes through the odontocete middle ear by means of two lever-arm systems, and the freely suspended involucrum forms the axis of one of these. In contrast, the pakicetids retain the land mammal morphology of the mandible, remingtonocetids and protocetids have a large mandibular foramen that indicates that the mandibular fat pad was present, and that the tympanic plate was functional during underwater hearing. The contact between periotic and tympanic bones in remingtonocetids

The cochlea is responsible for turning sound vibrations, converting them to nerve impulses, which is then sent to the brain. Once sent to the brain they are translated

When the musician first heard the sound of the dog barking the pinna, a part of the outer ear will channel the sound waves into the ear. Here the pinna collects the sound waves and passes it on to the eardrum, also known as the tympanic membrane. These vibrations from the eardrum are then sent to the middle inner ear, which is the chamber between the eardrum and cochlea which contains three tiny bones, the hammer, and stirrup. The bones, respectively known as the malleus, incus, and stapes then channel these sounds vibrations to the oval window which is the entrance to the cochlea which is a coiled, bony fluid-filled tube in the inner ear through which sound waves trigger nerve impulses. Through the motion of the stir-up the fluid that is within