Structure and Function of the Mammalian Ear

The tympanic membrane is a thin conical membrane that vibrates in the presence of sound and initiates the auditory process. It vibrates at the same frequency as the sound wave that hits it, and transmits these vibrations to the middle ear. The middle ear is made up of three small bones called small bones. They are hammer bones (hammer), anvil (anvil) and tibia (tibia). They amplify the vibration of the tympanic membrane and transmit these vibrations to the oval window of the inner ear.

An invertebrate such as an insect's "ear" is located on the leg of the chest and is associated with the respiratory tract called the trachea. The tympanic membrane has the same function as the tympanic membrane of the ear of the mammal. Like mammals, sound waves stimulate and vibrate membranes, but in insects it directly activates nerve impulses. (Barnes & Cawlow, 2002) Some insects also have an associated trachea that directs information on changes in insect internal pressure to the eardrum. When the right tympanic chamber is stimulated, a signal is sent to the left tympanic chamber via the trachea. The delay in stimulation between the left and right ears helps insects locate the direction from which the sound originates.

Mammalian expression systems can be used to produce mammalian proteins with the most natural structure and activity due to their physiologically relevant environment. This results in a high level of post-translational processing and functional activity. Mammalian expression systems are a preferred system for expressing mammalian proteins and can be used to produce proteins for assays based on antibodies, complex proteins and functional cells. However, these benefits are combined with more stringent cultural conditions.

Mammalian protein expression systems have the function of protein folding and posttranslational modification to bring the protein closer to the native protein and thereby obtain the same biological activity as the native protein. Thus, mammalian cell expression systems are most widely used in the development and manufacture of recombinant protein drugs, in particular for therapeutic monoclonal antibodies. Producing proteins with the correct quantity and quality is a fundamental requirement today. The use of mammalian cells for protein production seems to be increasing. The use of mammalian cells for recombinant protein expression systems allows for the introduction of appropriate protein folding, posttranslational modifications and product sets that are important for complete biological activity. This review article is entirely based on literature research.