Multiple Choice QuestionsAssertion : All motor neurons are efferent neurons.
Reason : Motor neurons conduct nerve impulses from the spinal cord to the brain.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false.
If both assertion and reason are false
Given is the diagrammatic representation of the sectional view of cochlea. Select the correct option regarding it.
A - Organ of corti-responsible for maintenance of balance of the body and posture.
B- Scala vestibuli-filled with perilymph that ends at the oval window.
C- Scala tympani-terminates at the round window which opens to the middle ear.
D- Basilar membrane - nerve impulses are generated against it.
Assertion: The optic nerves leave the eye at the point called blind spot.
Reason: Only cone are densely packed at the blind spot, hence is the name.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
Which of the following is correctly labelled
A: Reissner's membrane
B: Scala vestibuli
C : Basilar membrane
D: Tectorial membrane
The release of chemical messenger from synaptic vesicles is under the influence of these ion(s).
Cl-
Fe and S2+
Ca2+
Mg2+ and Sr2+
Assertion: Mylein sheath insulates the nerve fibre and prevents its depolarisation.
Reason: Nerve impulses are conducted more rapidly in non - myelinated nerve fibres than in myelinated ones.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false
C.
If assertion is true but reason is false.
In non-myelinated nerve fibres, the ionic changes are repeated over the membrane all along the length of the fibre. So, the action potential flows all along the membrane over the entire length of the fibre. But in myelinated fibres, the ionic changes and the consequent depolarisation can take place only at the nodes of Ranvier free from myelin sheath, because the myelin sheath between the nodes insulates the fibre and prevents its depolarisation. So, the action potential in effect jumps from one node to the next.This is called saltatory conduction of nerve impulses. Because of this, nerve impulses do not have to run all along the myelinated nerve fibre. This is why nerve impulses are conducted far more rapidly in myelinated fibres than in the non - myelinated ones.
Which of the following is true for the function disease in family A and B? of labelled parts in the diagram below?
A - Blind spot - Image is formed here
B - Fovea - No visual activity is present
C - Cornea - Helps to hold lens in place
D - Iris - Visible coloured portion of eye
Assertion : Corpus callosum connects the two cerebral hemispheres.
Reason : Association areas are responsible for complex functions like intersensory association of memory and communication.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are hue but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
Assertion : Auditory ossicles are small bones present in the cavity of inner ear.
Reason : Auditory ossicles maintain the balance of air pressure between two sides of ear drum.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false
If both assertion and reason are false.
Which of the following nerves arises from organ of Corti?
Olfactory nerve
Cochlear nerve
Abducens nerve
None of these
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