Biology 8 Lesson 51: Hearing Analyzer
1. Summary of theory
1.1. Structure of the ear
Ears are divided into: outer ear, middle ear and inner ear.
+ Outer ear:
- Ear lobe: responsible for catching sound waves.
- Ear canal: direction of sound waves.
The outer ear is limited by the tympanic membrane about 1cm in diameter.
The middle ear is a bony cavity consisting of:
- The chain of the ear bones, consisting of the hammer, incus, and stirrup bones, fits together.
The hammer bone is attached to the tympanic membrane, the stapes presses against a membrane that separates the middle and inner ear (called the oval peritoneum – an area 18-20 times smaller than the eardrum).
The space between the middle ear is connected with each other thanks to the tympanic tube, so the pressure on both sides of the eardrum is balanced.
+ Inner ear:
- Vestibular and semicircular canals: obtain information about the position and movement of the body in space
- Cochlea: Receives the stimulus of sound waves. Includes: cochlear cochlea inside with membranous cochlea.
+ The membranous cochlea is a membranous tube running along the bony cochlea and two and a half turns of the cochlea, including: vestibular membrane (upper), basal membrane (below) and lateral membrane.
+ On the muscle membrane there is a coocti organ: contains cells for hearing receptors.
1.2. Sound wave reception function
– Sound waves from the emitting sound source are picked up by the auricle, transmitted through the ear canal to vibrate the eardrum, to the ear bone chain and into the inner ear (vibrating the membrane of the “vaginal door”) => causing the movement of the external fluid and then the endolymph. in the cochlea, the membrane => acts on the Coocti organ to stimulate the auditory receptor cells located on the basal membrane in the region corresponding to the frequency and intensity of the sound waves => makes these cells excited and convert to pulses Nerves that transmit to the auditory area in the temporal lobes tell us about the sound that has been emitted.
1.3. Ear cleaning
– Regularly clean the ears, keep the ears clean
- Do not use sharp objects to pick your ears
- Keep your nose and throat clean to prevent ear disease.
- Avoid working in places that are too noisy or loud
- Limit the use of antibiotics that can cause tinnitus and hearing loss
2. Illustrated exercise
Lesson 1: The membranous cochlea is a membranous tube that runs along the bony ear canal and wraps around the cochlea two and a half times, consisting of
A. The vestibular membrane is superior, the basal membrane is below, and the lateral membrane is adjacent to the bony wall of the bony cochlea.
B. the muscular membrane is above, the vestibular membrane is below, and the lateral membrane is adjacent to the ear wall of the bony cochlea.
C. the muscular membrane is above, the lateral membrane is below, and the vestibular membrane is close to the ear wall of the bony cochlea.
D. the muscular membrane is below, the vestibular membrane is above, and the lateral membrane is close to the ear wall of the bony cochlea.
- Choose the answer: A
- Explanation: The membranous cochlea is a membranous tube that runs along the bony ear canal and wraps around the cochlea two and a half times, consisting of the vestibular membrane above, the basal membrane below, and the lateral membrane adjacent to the bony wall of the bony cochlea. .
Lesson 2: What is the cause of earwax?
A. It is secreted by the wax glands in the wall of the ear canal.
B. Due to moist ears.
C. Secreted by receptor cells.
D. Due to the secretion of fluid in the inner membrane of the ear.
- Choose the answer: A
- Explanation: Earwax is secreted by the wax glands in the wall of the ear canal.
Lesson 3: Why should exposure to loud noises or loud noises be avoided frequently?
Avoid exposure to places with strong noises or frequent strong noises that will affect nerves, reduce the elasticity of the eardrum, leading to indistinct hearing.
3.1. Essay exercises
Question 1: What is the process of receiving the excitation of sound waves?
Verse 2: Show the weight structure of the cochlea based on Figure 51-2.
Question 3: How does the process of receiving the stimulus of the duplex take place to help people hear?
Verse 4: Why can we determine if the sound is coming from the right or the left?
Question 5: Describe the receptor part of the auditory analyzer that helps us to receive high and low sound stimuli (bass), strong and weak (loud, low)?
3.2. Multiple choice exercises
Question 1: The ear is divided into 3 parts, which parts are they?
A. Auricle, middle ear, inner ear.
B. Outer ear, middle ear, inner ear.
C. Auricle, ear canal, eardrum.
D. Outer ear, eardrum, inner ear.
Verse 2: Which of the following is not part of the inner ear?
A. Semi-circular tube.
B. VIII nerve.
D. The eardrum.
Question 3: What is the function of the vestibule and semicircular canals?
A. Acquire information about the body’s position and movement in space.
B. Acquiring motion in space.
C. Acquire information about motion position in space.
D. Receiving position information of objects in space.
Verse 4: The outer ear is bounded by what part of the middle ear?
A. Semi-circular tube.
B. The eardrum.
C. Bone ear chain.
D. Eustachian tube.
Question 5: If the sound is in the right ear, which ear receives the sound wave first?
A. Left ear.
B. Right ear.
C. Both ears receive.
D. One of the ears.
After completing this lesson, you should meet the following requirements:
- Understand the components of the auditory analyzer.
- Describe the parts of the ear and the structure of the organ of Corti.
- Describe the process of acquiring sound sensations.
- Forming a sense of caring for ear hygiene