Windows of knowledge - class-IX
Description: windows of knowledge | |
Number of Questions: 50 | |
Created by: Arav Srivastava | |
Tags: windows of knowledge biology sensory organs of humans - sense organs neural control and coordination sense organs |
Dynamic balance is maintained by
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Maculae
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Cristae
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Organ of Corti
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Reissner's membrane
Sensory crista of ampulla of mammalian ear is connected with
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Sense of balance
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Sense of low hearing
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Sense of loud hearing
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Secretion of ear wax
The structures in a body that assist in body balance are located in
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Middle ear
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Inner ear
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Eustchain tubes
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None of the above
Which of the following membranes given us the ability to different pitches of sound?
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Membrane covering the round window
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Tympanic membrane
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Tectorial membrane
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Basilar membrane
The human ear can detect a wide range of frequencies, from the low rumbles of distant thunder to the high-pitched whine of a mosquito. The sensory cells that detect these sounds are called hair cells, named for the hair-like strands that cluster on their tops. Hair cells are spread across a flat surface called the basilar membrane, which is rolled like a carpet and tucked into a snail shell-shaped structure in the inner ear called the cochlea. Each of our roughly 16,000 hair cells is dedicated to a narrow frequency range. These cells are ordered along the basilar membrane according to the frequencies they detect.
Fill in the blank with correct option.
_________ db is the threshold of heating the faintest sound most of us can hear.
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$0$
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$1$
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$2$
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None of the above
Pitch of sound is determined by its
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Frequency
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Amplitude
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Speed
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Loudness
The amplitude is the SI unit of the pitch of the sound. So, the correct option is "Amplitude".
The membrane that gives us the ability to discriminate different pitches of sound is?
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Round window
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Oval window
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Tympanic membrane
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Ear pinna
Which of the following is an efficient organ for hearing in mammals?
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Internal ossicles
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Malleus and incus
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Cochlea
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Corpus callosum
The Cochlea is the auditory portion of the inner ear. It is a spiral-shaped cavity in the bony labyrinth, in humans making 2.5 turns around its axis, the modiolus.
Thus, the correct answer is option C.
The range of normal human hearing is in the range of
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10 Hz to 80 Hz
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50 Hz to 80 Hz
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50Hz to 15000 Hz
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15000 Hz and above
Which structure helps a person to maintain his equilibrium?
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Semicircular canals
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Cochlea
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Hammer
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Eustachian tube
The inner ear consists of two systems of canals which are namely cochlea and vestibular apparatus. The vestibular apparatus consists of three semicircular canals, cristae and two sacs called as saccule and utricle. Cochlea is the organ of hearing which contain mechanoreceptors for hearing. This makes option B incorrect. The three semicircular canals lie at right angle to each other in vestibular apparatus of inner ear and are filled with endolymph; this arrangement senses the change in movement (acceleration or deceleration) or position and maintain equilibrium. The mechanism includes movement of cupula in response to movement of endolymph within the canal causing the bending of cilia to generate the nerve impulse. This makes option A correct. Hammer is the one of the three ossicles of the middle ear which is concerned with amplification of air pressure while passing it from the inner surface of tympanic membrane via incus to stapes. This makes option C incorrect. The eustachian tube extends from each middle ear to nasopharynx and permits the equalization of air pressure. This makes option D incorrect. Correct answer is A.
Semicircular canals in vertebrate are responsible for
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Detection of change of atmospheric pressure
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Orientation of animal with regard to sun
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Maintenance of balance when the organism is in motion
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Regulation of speed of animal
Receptors that sense the change in atmospheric pressure are classified under mechanoreceptors. Three pressure receptors are namely Pacinian corpuscles, Ruffini endings and Krause end bulbs which are located in skin. This makes option A incorrect. The three semicircular canals lie at right angle to each other in vestibular apparatus of inner ear and are filled with endolymph; this arrangement senses the change in movement (acceleration or deceleration) or position. The mechanism includes movement of cupula in response to movement of endolymph within the canal causing the bending of cilia to generate the nerve impulse. This makes option C correct and option D incorrect. Migratory birds and animals have receptors in their brain which are activated by direction of sunlight and orient their body at certain angle in relation to sun. This makes option B incorrect. Correct answer is C.
You are riding a bicycle and take a sudden turn around a sharp corner. The organs involved in the maintenance of balance is
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Medulla oblongata
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Semicircular canals
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Cerebrum
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Optic chiasma
You are riding a bicycle and take a sudden turn around a sharp corner. The organ involved in the maintenance of balance is
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Medulla oblongata
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Semicircular canals
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Cerebrum
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Optic chiasm
Semicircular canals in vertebrate are responsible for
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Detection of change of atmospheric pressure
-
Orientation of animal with regard to sun
-
Maintenance of balance when the organism is in motion
-
Regulation of speed of animal
Receptors that sense the change in atmospheric pressure are classified under mechanoreceptors. Three pressure receptors are namely Pacinian corpuscles, Ruffini endings and Krause end bulbs which are located in skin. This makes option A incorrect. The three semicircular canals lie at right angle to each other in vestibular apparatus of inner ear and are filled with endolymph; this arrangement senses the change in movement (acceleration or deceleration) or position. The mechanism includes movement of cupula in response to movement of endolymph within the canal causing the bending of cilia to generate the nerve impulse. Migratory birds and animals have receptors in their brain which are activated by direction of sunlight and orient their body at certain angle in relation to sun. Thus, the correct answer is option C.
The impulse of sound is conducted to the brain by
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Olfactory nerve
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Auditory nerve
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Optic nerve
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Trachea nerve
The olfactory nerve is the second cranial nerve which transmits the nerve impulses from olfactory receptors, receptors of sense the smell that are located in nasal epithelium of roof of the nasal cavity, to the brain.
Statoreceptors are meant for sensing
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Taste
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Heat
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Balance
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Sound waves
Statoreceptors are the receptors for sense of balance and equilibrium. They are present in vestibular apparatus of inner ear.
Which structure helps a person maintain his equilibrium?
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Semicircular canals
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Cochlea
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Hammer
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Eustachian tube
The inner ear consists of two systems of canals which are namely cochlea and vestibular apparatus. The vestibular apparatus consists of three semicircular canals, cristae and two sacs called as saccule and utricle. The cochlea is the organ of hearing which contains mechanoreceptors for hearing. This makes option B incorrect. The three semicircular canals lie at the right angle to each other in vestibular apparatus of the inner ear and are filled with endolymph; this arrangement senses the change in movement (acceleration or deceleration) or position. The mechanism includes movement of cupula in response to movement of endolymph within the canal causing the bending of cilia to generate the nerve impulse. Hammer is one of the three ossicles of the middle ear which is concerned with amplification of air pressure while passing it from the inner surface of tympanic membrane via incus to stapes. The eustachian tube extends from each middle ear to nasopharynx and permits the equalization of air pressure. Thus, the correct answer is option A.
Which of the following term is used for sound below 20 Hz?
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Infrasound
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Ultrasound
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Echo
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None of the above
The human ear can generally hear sounds with frequencies between 20 Hz and 20 kHz. Although hearing requires an intact and functioning auditory portion of the central nervous system as well as a working ear, human deafness most commonly occurs because of abnormalities of the inner ear, rather than in the nerves or tracts of the central auditory system. Sound below 20 Hz is considered infrasonic, which the ear cannot process. Therefore, the correct answer is option A.
Hearing in rabbit is better than frog. One reason for this is that rabbit has
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Three semicircular canal
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Vibratile tympanic membrane
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Movable pinna
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Both fenestra ovalis and eustachian tubes
Ear of frog consists of only two parts - middle and internal ear but no external ear. In the rabbit, ear has three regions which are external, middle and internal. External ears consist of the pinna (auricle) and auditory canal (external auditory meatus). Pinna is provided with voluntary muscle and is supported by elastic fibrocartilage. Pinna helps in collecting the sound waves. So, hearing in the rabbit is better than the frog.
The true sense of equilibrium in mammals are situated in the
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Malleus
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Utriculus
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Eustachian tubes
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Semicircular canal
The semicircular canals are three canals used to provide information to the brain on directional balance and equilibrium. Each canal is lined with cilia and filled with a fluid called endolymph. As the head and body move, the fluid moves and pushes the cilia back and forth to create a motion sensor.
Hearing is controlled by
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Frontal lobes
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Parietal lobes
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Temporal lobes
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Occipital lobes
Static balance is maintained by
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Maculae
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Cristae
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Organ of Corti
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Reissner's membrane
Statoreceptors are located in
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Cristae
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Maculae
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Both A and B
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Cochlea
Part of ear concerned with hearing is
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Reissner's membrane and tectorial membrane
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Basilar membrane and tectorial membrane
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Reissner's membrane and basilar membrane
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Ampulla
The sense of equilibrium is determined by
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Basilar membrane of cochlea
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Tectorial membrane of cochlea
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Sensory crista of ampulla
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Sensory cells of organ of Corti
Sound is transmitted from middle ear to internal ear due to
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Vibrations of tympanum
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Vibrations of stapes
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Striking of stapes
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All of the above
Receptor cells for balancing occur in human ear in
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Malleus, incus and stapes
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Utriculus, sacculus and semicircular canals
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Organ of Corti
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Eustachian tube
Pressure is maintained on two sides of ear drum by
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Auditory ossicles
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Membranous labyrinth
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Eustachian tube
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Cochlea
Correct sequence of regions in organisation of auditory mechanoreceptor organ is
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Pinna - Tympanic membrane - Auditory canal - Cochlea - Malleus - Incus - Stapes - Auditory nerve
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Pinna - Malleus - Incus - Stapes - Auditory canal - Tympanic membrane - Cochlea - Auditory nerve
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Pinna - Auditory canal - Tympanic membrane - Malleus - Incus - Stapes - Cochlea - Auditory nerve
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Pinna - Cochlea - Tympanic membrane - Auditory membrane - Auditory canal - Incus - Malleus - Stapes - Cochlea - Auditory nerve
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Pinna - Tympanic membrane - Auditory canal - Incus - Malleus - Stapes - Cochlea - Auditory nerve.
- The outermost part of human ear is called pinna (external ear).
- Pinna is followed by auditory canal. It is a tube by which pinna is connected to middle ear.
- The auditory canal extends from pinna to tympanic membrane (ear drum).
- Tympanic membrane is followed by three ear ossicles, malleus, incus and stapes.
- Stapes is attached to oval window of cochlea and transfers the vibrations to the fluid of cochlea. Cochlea is a part of inner ear.
- Inner ear contains vestibular apparatus and auditory nerve along with cochlea.
Specific receptors responsible for the balance of the body and posture are __________.
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Organ and Corti
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Crista and macula
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Basilar membrane
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Tectorial membrane
Static equilibrium is maintained by
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Sacculus
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Utriculus
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Semicircular canals
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Both A and B
Which one is used in balancing?
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Organ of Corti
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Vestibular region
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Middle ear
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Cochlea
Identify the wrong statement regarding the mechanism of hearing.
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External ear receives and directs the sound waves to ear drum
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Vibrations produced in ear drum are transmitted through ear ossicles and oval window to fluid-filled inner ear
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Movement of basilar membrane bends the hair cells
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Nerve impulses are generated and transmitted by efferent fibres to the auditory cortex of brain
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Cerebellum integrates information from semicircular canals of ear and auditory system.
- When sound waves from the environment enter the external ear, they are directed to ear drum (tympanic membrane).
- The ear drum vibrates on receiving sound waves and the vibrations are sent to oval window through ear ossicles which are malleus, incus and stapes.
- From the oval window, these vibrations are passed onto fluid of cochlea where waves are generated into lymph due to these vibrations.
- These waves generate vibrations in the basilar membrane which bend the hair cells and press them against the tectorial membrane.
- This results in the generation of nerve impulses in afferent neurons which are transmitted by afferent fibres to auditory cortex of brain.
- The impulses are analysed and recognised in brain.
The correct path followed by sound waves from external ear to inner ear is
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Ear drum - basilar membrane - auditory ossicles - fluid of cochlea - hair cells
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Ear drum - auditory ossicles - fluid of cochlea - basilar membrane - hair cells
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Ear drum - hair cells - auditory ossicles - basilar membrane - fluid of cochlea
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Ear drum - fluid of cochlea - auditory ossicles - hair cells - basilar membrane
- Sound waves from the environment enter the external ear and are directed to ear drum (tympanic membrane).
- The ear drum vibrates on receiving sound waves and the vibrations are sent to oval window through ear ossicles which are malleus, incus and stapes.
- From the oval window, these vibrations are passed onto fluid of cochlea where waves are generated into lymph due to these vibrations.
- These waves generate vibrations in the basilar membrane which bend the hair cells and press them against the tectorial membrane.
Maculae maintains
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Static equilibrium
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Dynamic equilibrium
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Both A and B
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None of these
Maculae are the specialized mechanoreceptors within the utricle and saccule for the detection of static equilibrium, they make use of the hair cells to detect the movements of the otolithic membrane, the nerve impulses thus generated and transmitted along the vestibular branch of the cranial nerve to the central nervous system.
The balancing organ of ear is
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Lagena and Sacculus
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Semicircular canal and Utriculus
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Semicircular canal and Ossicles
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Otolith and Lagena
The structures in a human body that assist in body balance are located in the
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Outer ear
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Middle ear
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Inner ear
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Eustachian tube
The sensory receptors that respond to sound, develop receptor potentials when their
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Hairs are absent
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Pigments absorb pressure
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Surface proteins are altered by a change in pH
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Sodium-potassium pumps become deactivated.
Macula maintains _______________.
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Static equilibrium
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Dynamic equilibrium
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Both (a) and (b)
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None of these
Maculae detect changes in the body with respect to gravity (static equilibrium) and in the movement in one direction (linear acceleration). So, the correct answer is (A).
Membranous labyrinth is concerned with
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Sensing
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Hearing with balancing
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vagus nerve
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All of the above
The functional components of the membranous labyrinth involved in the sensations of static and dynamic equilibrium are a system of thin walled, intercommunicating tubes and ducts situated within the petrous part of the temporal bone at the base of the skull. There are five vestibular structures, each containing a specialized mechanoreceptor, (maculae), within the utricle and saccule, and cristae within the ampulla of the superior, horizontal, and posterior semicircular canals.
Sensation of hearing is produced as a result of the
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Presence of the helicotrema
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Vibrations set in the external auditory meatus
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Vibrations of the ear ossicles
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Nerve impulses generated by the hair cells of the organ of Corti
Within the bony labyrinth, is the membranous labyrinth; filled with the fluid called as endolymph. The membranous labyrinth within the cochlea contains the organ of Corti containing the inner and outer hair cells, that generate the nerve impulses required for hearing. Nerve impulses generated in the inner ear travel along the vestibulocochlear nerve (cranial nerve VIII) to the brain.
Which organ in our body acts as dual receptor?
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Nose
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Ear
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Tongue
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Eye
Ear acts as the dual receptor in the following ways:
- the cochlea contains the organs of Corti which receive the mechanical sound waves and converts them into hearing impulse.
- the vestibular apparatus contains the semicircular canals that sense the dynamic balance position and the utricle and saccule sense the static balance of the body.
Which structure helps a person to maintain equilibrium?
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Cochlea
-
Eustachian tube
-
Semicircular canals
-
Hammer like bone
The semicircular canals are three canals used to provide information to the brain on directional balance. Each canal is lined with cilia and filled with fluid, called as endolymph. As the head and body move, the fluid moves and pushes the cilia back and forth to create a motion sensor. The three main parts of the semicircular canals are the horizontal, posterior and superior. The superior is responsible for head rotation, the posterior canal detects movement and rotation on the sagittal plane, and the horizontal senses on a vertical basis.
The internal ear of rabbit originates from
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Ectoderm
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Endoderm
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Mesoderm
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All of the above
The first part of the ear to develop is the inner ear. Its appearance occurs around the 22$^{nd}$ day of the embryo's development, originating from the ectoderm germinative layer.
Which one of the following is correct?
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Semicircular canal- Balancing
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Cochlea- Hearing
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Utriculus and sacculus- Balancing
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All of the above
- Semicircular canals are three tiny fluid-filled tube in our inner ear that helps to keep our balance.
- Cochlea transforms the sound or vibration of cochlear liquid into neural signals.
- Utriculus and Sacculus are part of balancing apparatus of ear located within the vestibule of the bony labyrinth which respond to change in the position of the head with respect to gravity (linear acceleration).
Body balance during dynamic condition is initiated by which structure?
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Otoconia
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Cupula
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Stereocilia of crista
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Kinocilium of maculae
The cupula is a structure in the vestibular system, providing the sense of spatial orientation. The cupula is located within the ampullae of each of the three semicircular canals. Part of the crista ampullaris, the cupula has embedded hair cells that have several stereocilia associated with each kinocilium. The cupula itself is the gelatinous component of the crista ampullaris that extends from the crista to the roof of the ampullae. When the head rotates, the endolymph filling the semicircular ducts initially lags behind due to inertia. As a result, the cupula is deflected opposite the direction of head movement. As the endolymph pushes the cupula, the stereocilia are bent as well, stimulating the hair cells within the crista ampullaris. After a short time of continual rotation, however, the endolymphs acceleration normalizes with the rate of rotation of the semicircular ducts. As a result, the cupula returns to its resting position and the hair cells cease to be stimulated. This continues until the head stops rotating which simultaneously halts semicircular duct rotation.
Cochlea of mammalian internal ear is concerned with
-
Balance of body posture
-
Both balance and hearing
-
Hearing
-
Perception of atmospheric pressure
Which structure helps a person to maintain his equilibrium?
-
Cochlea
-
Hammer
-
Semicircular canals
-
None of the above
A semicircular canal or a semicircular duct is one of three semicircular, interconnected tubes located inside each ear. The three canals are the horizontal semicircular canal (also known as the lateral semicircular canal), superior semicircular canal (also known as the anterior semicircular canal) and the posterior semicircular canal (also known as the inferior semicircular canal).
It helps in regulating body balance. Endolymph, which is present in the ear plays a major role in regulating body balance.
Deformation of sensory dendrites is required to establish a nerve impulse in all of the following except
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gustatory hair cells
-
organ of Corn
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Pacinian corpuscles
-
lateral line organs
The sensory nervous system and the motor nervous system are a part of the nervous system responsible for the processing of sensory information. A sensory system consists of sensory neurons, neural pathways, and parts of the brain involved in sensory perception.
Following is a list of the events (in a random order) that lead to the formation of an auditory impulse.
(i) Vibration is transferred from the malleus to the incus to the stapes.
(ii) Basilar membrane moves up and down.
(iii) Nerve impulse is transmitted in cochlear nerve to auditory cortex of brain for impulse analysis and recognitions.
(iv) Sound waves pass through ear canal.
(v) Stereocilia of hair cells of organ of Corti rub against tectorial membrane.
(vi) Sound waves cause ear drum to vibrate.
(vii) Nerve impulse is generated.
(viii) Vibrations move from fluid of vestibular canal to the fluid of tympanic canal.
(viii) Vibrations move from fluid of vestibular canal to the fluid of tympanic canal.
(ix) Membrane at oval window vibrates.
Which of the following options represents these events in a correct order?
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(iv), (vi), (i), (ix), (viii), (ii), (v), (vii), (iii)
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(i), (ii), (iii), (iv), (v), (vi), (vii), (viii), (ix)
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(ix), (viii), (vii), (vi), (v), (iv), (iii), (ii), (i)
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(iv), (vi), (i), (viii), (ix), (ii), (v), (vii), (iii)
The ear not only detects sound but also notes its direction, judges its loudness and determines is pitch.Auditory impulse form through different steps: