Concept explainers
Mark the following statements as true or false. If a statement is false, correct it to make a true statement.
a. The somatic sensory division of the PNS detects sensory stimuli from the organs in the thoracic and abdominopelvic cavities.
b. The somatic motor division of the PNS consists of lower motor neurons that directly innervate skeletal muscle fibers.
c. The visceral motor division is also known as the autonomic nervous system and maintains homeostasis of many physiological variables.
d. The term nerve is the equivalent of the term neuron.
e. There are 31 pairs of spinal nerves and 12 pairs of cranial nerves.
To review:
Whether the following statements are true or false:
1. The somatic sensory division of the PNS detects sensory stimuli from the organs in the thoracic and abdominopelvic cavities.
2. The somatic motor division of the PNS consists of lower motor neurons that directly innervate the skeletal muscle fibers.
3. The visceral motor division is also known as the autonomic nervous system and maintains homeostasis of many physiological variables.
4. The term ‘nerve’ is the equivalent of the term ‘neuron’.
5. There are 31 pairs of spinal nerves and 12 pairs of cranial nerves.
Introduction:
The peripheral nervous system acts as a link which bridges the CNS (central nervous system) with the body and outer environment. In order to link them, it first detects the sensory parts of the stimuli and carries them to the CNS as a sensory input. The CNS works on the input and then distributes the impulses by means of the PNS (peripheral nervous system) to the effectors to generate a motor output. In this case, the effectors are the muscle cells and glands.
Explanation of Solution
a. The statement “The somatic sensory division of the PNS detects sensory stimuli from the organs in the thoracic and abdominopelvic cavities”is false. The correct statement is the somatic sensory division of the PNS detects sensory stimuli from the structures of musculoskeletal system. In fact, they detect the stimuli from the skin and structures of the musculoskeletal system.
b. The statement “The somatic motor division of the PNS consists of lower motor neurons that directly innervate skeletal muscle fibers” is true. In the true sense, the somatic motor division of the PNS consists ofa lower type of motor neurons which are in direct contact with the skeletal muscle fibers.
c. The statement “The visceral motor division is also known as the autonomic nervous systemwhichmaintains homeostasis of many physiological variables” is true. The visceral motor division is also known as the autonomic nervous system which maintains the homeostasis state of many variables which are physiological in nature by controlling the involuntary motor functions of the body.
d. The statement “The term nerve is the equivalent of the term neuron” is true. It is foundthat a nerve contains numerous neurons which are connected to each other by a tissue.
e. The statement “There are 31 pairs of spinal nerves and 12 pairs of cranial nerves” is true. It widely known that there are 31pairs of spinal nerves and 12 pairs of spinal nerves in the human body.
Thus, it can be concluded that the statements(b), (c),(d) and(e) are true according to the reasons provided and the statement (a) is false.
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Chapter 13 Solutions
HUMAN ANAT&PHYS&MOD MA&P/ET&PHOTO ATLAS
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