I have 3 questions.

What part of the ear transmits vibrations to the hair cells of the Organ of Corti?

What is the fluid that takes the vibrations out of theear and out of the round window?

Which of these statements would NOT be true?

1. the stapes transmists vibration to the inner ear

2. vibrations inthe fluid of the cochlea cause bending oft he hair cells

3. the eardrume transmits vibration to the mastoid bone

4. the middle ear contains the small bones of the ear

http://content.answers.com/main/content/img/oxford/Oxford_Body/019852403x.hearing.1.jpg

Where is the mastoid bone?

http://hyperphysics.phy-astr.gsu.edu/hbase/sound/cochlea.html

Let's tackle each question one by one.

Question 1: What part of the ear transmits vibrations to the hair cells of the Organ of Corti?

The part of the ear that transmits vibrations to the hair cells of the Organ of Corti is called the basilar membrane. This membrane is located in the cochlea, which is the spiral-shaped structure in the inner ear responsible for translating sound waves into electrical signals that can be interpreted by the brain.

To find the answer to this question, you can start by understanding the structure and function of the ear. The outer ear collects sound waves, which then travel through the ear canal to the eardrum (tympanic membrane). The eardrum vibrates in response to the sound waves. These vibrations are then transmitted to the three tiny bones in the middle ear called the ossicles: the malleus (hammer), incus (anvil), and stapes (stirrup). The stapes bone connects to the oval window, which is located between the middle and inner ear.

From here, the vibrations pass from the oval window to the fluid-filled cochlea. Within the cochlea, the basilar membrane supports the organ of Corti, which contains the hair cells responsible for converting the vibrations into electrical signals that can be transmitted to the brain. Therefore, the vibrations are transmitted from the stapes bone to the basilar membrane, which then stimulates the hair cells in the organ of Corti.

Question 2: What is the fluid that takes the vibrations out of the ear and out of the round window?

The fluid that takes the vibrations out of the ear and out of the round window is called perilymph. The cochlea, which is part of the inner ear, is filled with two different fluids: perilymph and endolymph.

To find the answer, it is important to understand the anatomy of the inner ear. After passing through the oval window, the vibrations enter the cochlea, where they travel through the fluid-filled chambers. The vibrations move through the perilymph, which is found in the scala vestibuli and scala tympani, two of the three chambers within the cochlea. These vibrations cause movements in the fluid and stimulate the hair cells located on the basilar membrane in the organ of Corti.

The round window is a flexible membrane located at the end of the scala tympani. Its purpose is to relieve the pressure caused by the fluid movement within the cochlea. So, the vibrations that have passed through the basilar membrane exit the cochlea and dissipate through the round window, ultimately leaving the ear.

Question 3: Which of these statements would NOT be true?

1. The stapes transmits vibrations to the inner ear.
2. Vibrations in the fluid of the cochlea cause bending of the hair cells.
3. The eardrum transmits vibrations to the mastoid bone.
4. The middle ear contains the small bones of the ear.

To determine which statement is not true, let's analyze each option one by one:

1. The stapes transmits vibrations to the inner ear.
This statement is true. As mentioned earlier, the stapes bone transmits vibrations from the middle ear to the inner ear. It connects to the oval window, which is one of the entry points to the fluid-filled cochlea.

2. Vibrations in the fluid of the cochlea cause bending of the hair cells.
This statement is true. As sound vibrations pass through the cochlea's perilymph-filled chambers, they cause movements in the fluid. These fluid movements bend the hair cells located on the basilar membrane within the organ of Corti. The bending of hair cells is crucial for converting mechanical vibrations into electrical signals.

3. The eardrum transmits vibrations to the mastoid bone.
This statement is not true. The eardrum, or tympanic membrane, does not transmit vibrations to the mastoid bone. Its role is to vibrate in response to sound waves and transmit these vibrations to the middle ear's three small bones: the malleus, incus, and stapes.

4. The middle ear contains the small bones of the ear.
This statement is true. The middle ear does contain the three small bones of the ear, which are also known as the ossicles. These bones, namely the malleus, incus, and stapes, transmit sound vibrations from the eardrum to the inner ear.

Therefore, the answer to the third question is statement number 3: "The eardrum transmits vibrations to the mastoid bone," as it is not true.