Q.3. Describe the structure of the internal and middle ear.
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The inner ear has two openings into the middle ear, both covered by membranes

Explanation:

The oval window lies between the middle ear and the vestibule, whilst the round window separates the middle ear from the scala tympani (part of the cochlear duct)

QUESTION:

Describe the structure of the internal and middle ear.

Ears are a pair of a statoacoustic organ that helps in balancing and hearing. The human ear includes – the middle ear, the inner ear, and the internal ear. The pinna is a part of the auditory system and forms the external ear. The middle ear has 3 bones – the malleus(hammer), the stapes(stirrup) and incus(anvil) which are attached in a chain-like pattern. The stapes is connected to the oval window of cochlea and the malleus is connected to the tympanic membrane. These three bones or ossicles raises the productivity of communication of sound waves to the inner ear. The middle ear leads to the Eustachian tube that bridges along with the pharynx and controls the force between the outside and the middle ear. The inner ear comprises a labyrinth of chambers filled with fluids inside the temporal bone of the skull. The labyrinth has 2 parts – the membranous and the bony labyrinth(series of channels). Inside the channels lies the membranous labyrinth which is girdled by a fluid known as perilymph and filled with a fluid called endolymph. The labyrinth has a coiled structure called the cochlea. Which has 2 large canals – upper vestibular canal and a lower tympanic canal that is divided by a small cochlear duct. Both canals contain the perilymph with endolymph in the cochlear duct. Towards the base of the scala vestibuli, the membranous labyrinth walls are in sync with the fenestra ovalis and at the lower end of the scala tympani is the fenestra rotunda.

americans began to notice growing differences between the northern and southern sections of the country. there were more people living in cities in the north, which made it more urban. more people lived on farms in the south, which made it more rural. while many people were farmers in the northern states, there were now other ways to make a living, such as working in mechanical cotton gins factories manufacturing cloth, tools and other goods. people in the north supported high tariffs on goods imported from europe because the extra cost encouraged people to “buy american” instead. in the southern states, planters did not like tariffs because they sold most of their production to europe and bought their tools from there as well. southerners believed the protective tariff was something that only northern factory owners keep their profits high. so the southern politicians came up with an idea. they would opt out. they would simply ignore the protective tariff. it was ‘null and void’ in south carolina. the state would not collect the taxes on goods imported into south carolina, no matter what the president said they had to do. this decision led to the nullification crisis.

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