Nervous System

    Nervous System
    What are the major types of nerve cells in the CNS?
    Multipolar are most common in the CNS. Motor neurons, whose cell bodies lie within the spinal cord, are multipolar.
    Author: rikazzz Comment
    Nervous System
    Which part of the brain contains the cells that allow us to consciously control voluntary muscle movements?
    The precentral gyrus of the frontal lobe is anterior to the central sulcus (which divides the frontal lobe from the parietal lobes) and is our primary motor area.
    Author: rikazzz Comment
    Nervous System
    What are the names of the two types of photoreceptors in the retina?
    Cone cells are sensitive to colour while rod cells are more sensitive in scotopic (low light) conditions. Ganglion and bipolar cells are not sensitive to light. The fovea centralis is the central region of the macula lutea of the retina.
    Author: rikazzz Comment
    Nervous System
    Which of the following would conduct an action potential with the greatest speed?
    Myelinated fibres allow for faster conduction speed as does greater diameter of axon.
    Author: rikazzz Comment
    Nervous System
    To what part of the nervous system does the somatic nervous system belong?
    The somatic nervous system carries commands from the brain (efferent impulses) to the muscles and glands – which are in the peripheries of the body.
    Author: rikazzz Comment
    Nervous System
    Sound level (measured in decibels, dB) is a subjective measure of the loudness of a sound. A sound of 90 dB:
    This sound pressure level (or perhaps even 85 dB) will produce hearing damage with long-term exposure. The decibel is not a statement about frequency. 0 dB is the threshold of human hearing. Different frequencies if all played at 90 dB would be perceived as different in loudness.
    Author: rikazzz Comment
    Nervous System
    To what does the following description apply? “An unlearned and involuntary but predictable motor response to a stimulus that is rapid and does not involve any processing by the brain”.
    Spinal reflexes happen without the involvement of conscious or unconscious decision-making by the brain.
    Author: rikazzz Comment
    Nervous System
    What is the blood-brain barrier?
    The BBB is the endothelial cells of the capillaries (which are joined by tight junctions), their basement membrane and the enveloping astrocytic feet of the astrocytes (one of the cell types called neuroglia).
    Author: rikazzz Comment
    Nervous System
    What is that part of the nervous system that carries commands to the skeletal muscles called?
    The somatic NS carries motor commands to the skeletal muscles (our soma).
    Author: rikazzz Comment
    Nervous System
    Which neurotransmitter is released by all parasympathetic neurons?
    All parasympathetic neurons release ACh as a neurotransmitter. Nicotine and muscarine are not produced by the body.
    Author: rikazzz Comment