Nervous System

    Nervous System
    What part of the brain receives sensory input before passing it on to another part of the brain for interpretation or action?
    The thalamus relays visual and auditory information.
    Author: rikazzz Comment
    Nervous System
    What is the purpose of a neurotransmitter?
    Choices C and D are also correct, but B is the more general answer.
    Author: rikazzz Comment
    Nervous System
    In nerve fibres with myelin sheaths, which of the following is true about the electrical conduction?
    The myelin sheath increases the speed of conduction along an axon as the action potential is regenerated when migrating Na ions reach the next node. It “jumps” (saltates) from one node to the next.
    Author: rikazzz Comment
    Nervous System
    Which statement about the neurotransmitter acetylcholine (ACh) is NOT correct?
    In fact norepinephrine (not ACh) is released by most ANS-SD postganglionic fibres, i.e. at second synapse. Choices A, C and D are true.
    Author: rikazzz Comment
    Nervous System
    Which of the lists of structures include all of the central nervous system?
    There are five distinct structures in the CNS. Autonomic nerves, motor and sensory neurones and special sense organs are not part of the CNS.
    Author: rikazzz Comment
    Nervous System
    What is linked to the posterior grey horn of the spinal cord?
    Posterior means dorsal. The dorsal root carries axons of sensory neurons.
    Author: rikazzz Comment
    Nervous System
    What is the likely result of an injury that severs the spinal cord between C5 and C6?
    Spinal nerves below the break cannot pass on impulses from the brain. So quadriplegia results because the spinal nerves that innervate the limbs leave the spinal cord below the level of the spinal cord break (except for some brachial nerves that leave at C5). Fortunately, the phrenic nerve, which innervates the diaphragm, leaves the spinal cord at C3, C4 and C5 so will still carry impulses from the brain. So breathing will continue.
    Author: rikazzz Comment
    Nervous System
    What is the function of the corpus callosum?
    Commissural fibres pass through the corpus callosum that connect corresponding areas in the two hemispheres.
    Author: rikazzz Comment
    Nervous System
    From what part(s) of the body does the vagus nerve originate?
    The vagus nerve is cranial nerve X, so originates from the medulla oblongata of the midbrain. It is not a spinal nerve.
    Author: rikazzz Comment
    Nervous System
    Which word correctly completes the statement: “All motor neurons are…”?
    Motor neurones (that innervate muscles) are multipolar.
    Author: rikazzz Comment