Biology
Nervous System and Neurons
1,224 Questions
The nervous system and neurons section covers the structural and functional aspects of the human nervous system. Topics include nerve fibers, the myelin sheath, and sympathetic nervous system functions. This material is crucial for general science preparation in various competitive exams.
Neuron structureMyelin sheath productionSympathetic nervous systemCranial and spinal nervesParasympathetic functions
Nervous System and Neurons Questions
Nerve impulse generation is a
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Physical process
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Chemical process
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Effected process
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Electro-chemical process
D
Correct answer
Explanation
A nerve impulse is a way nerve cells (neurons) communicate with one another. Nerve impulses are mostly electrical signals along the dendrites to produce a nerve impulse or action potential. The action potential is the result of ions moving in and out of the cell.
Destruction of the anterior horn cells of the spinal cord would result in loss of
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Sensory impulses
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Voluntary motor impulses
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Commissural impulses
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Integrating impulses.
B
Correct answer
Explanation
Anterior horn cells are the ventral (front) grey matter section of the spinal cord which contains motor neurons that affect the skeletal muscles. It is also known as anterior grey column, ventral horn. The anterior grey column is the column where the cell bodies of alpha motor neurons are located. The destruction of the anterior horn cells of the spinal cord would result in loss of voluntary motor impulses because it is mainly related to motor impulses.
So, the correct answer is option B.
What is the process by which neurotransmitters are released from the presynaptic neuron?
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Exocytosis
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Endocytosis
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Diffusion
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Active transport
A
Correct answer
Explanation
Neurotransmitters are released from the presynaptic neuron through a process called exocytosis, in which vesicles containing neurotransmitters fuse with the presynaptic membrane and release their contents into the synaptic cleft.
What is the role of neurotransmitter receptors in synaptic transmission?
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To bind to neurotransmitters and initiate a response in the postsynaptic neuron
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To produce neurotransmitters
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To regulate the release of neurotransmitters
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To transport neurotransmitters across the synaptic cleft
A
Correct answer
Explanation
Neurotransmitter receptors are located on the postsynaptic neuron and bind to neurotransmitters, triggering a response in the postsynaptic neuron.
What is the term for the space between the presynaptic and postsynaptic neurons?
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Synaptic cleft
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Synaptic junction
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Synaptic vesicle
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Synaptic terminal
A
Correct answer
Explanation
The synaptic cleft is the space between the presynaptic and postsynaptic neurons where neurotransmitters are released and received.
What is the role of presynaptic vesicles in synaptic transmission?
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To store neurotransmitters
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To produce neurotransmitters
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To regulate the release of neurotransmitters
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To transport neurotransmitters across the synaptic cleft
A
Correct answer
Explanation
Presynaptic vesicles are located in the presynaptic neuron and store neurotransmitters until they are released into the synaptic cleft.
What is the role of glial cells in synaptic transmission?
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To regulate the release of neurotransmitters
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To produce neurotransmitters
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To remove neurotransmitters from the synaptic cleft
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To transport neurotransmitters across the synaptic cleft
C
Correct answer
Explanation
Glial cells, such as astrocytes, help to remove neurotransmitters from the synaptic cleft, thereby regulating synaptic transmission.
What is the term for the electrical signal that is generated in the postsynaptic neuron in response to neurotransmitter binding?
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Action potential
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Synaptic potential
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Neurotransmitter potential
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Ionotropic potential
B
Correct answer
Explanation
The electrical signal that is generated in the postsynaptic neuron in response to neurotransmitter binding is called a synaptic potential.
What is the role of the nerve functor in the study of higher categories?
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The nerve functor converts a higher category into a simplicial set.
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The nerve functor converts a simplicial set into a higher category.
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The nerve functor establishes a correspondence between higher categories and simplicial sets.
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None of the above.
C
Correct answer
Explanation
The nerve functor establishes a correspondence between higher categories and simplicial sets, allowing for the study of higher categories through the lens of simplicial topology.
What is the control center of the nervous system?
A
Correct answer
Explanation
The brain is the control center of the nervous system and is responsible for processing information, making decisions, and controlling movement.
What are the three types of nerves?
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Sensory nerves, motor nerves, and mixed nerves
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Frontal nerves, parietal nerves, and occipital nerves
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Temporal nerves, limbic nerves, and basal ganglia nerves
A
Correct answer
Explanation
The three types of nerves are sensory nerves, motor nerves, and mixed nerves.
What is the function of sensory nerves?
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To send messages from the brain to the rest of the body
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To send messages from the rest of the body to the brain
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Both a and b
B
Correct answer
Explanation
Sensory nerves are responsible for sending messages from the rest of the body to the brain.
What is the function of motor nerves?
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To send messages from the brain to the rest of the body
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To send messages from the rest of the body to the brain
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Both a and b
A
Correct answer
Explanation
Motor nerves are responsible for sending messages from the brain to the rest of the body.
What is the function of mixed nerves?
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To send messages from the brain to the rest of the body
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To send messages from the rest of the body to the brain
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Both a and b
C
Correct answer
Explanation
Mixed nerves are responsible for sending messages from the brain to the rest of the body and for sending messages from the rest of the body to the brain.
What is the largest nerve in the human body?
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Sciatic nerve
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Median nerve
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Ulnar nerve
A
Correct answer
Explanation
The sciatic nerve is the largest nerve in the human body and runs from the lower back down the back of the leg.