Concept explainers
Videos
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.
Want to see more full solutions like this?
Chapter 13 Solutions
Human Anatomy & Physiology (2nd Edition)
- Sensory neurons transmit information towards the central nervous system. Which of the following is true concerning the movement of peripheral- information towards the central nervous system? A. Dendrites of the sensory neurons synapse with interneurons of the spinal cord. B. Axons of the sensory neurons synapse with motor neurons of the muscles involved in the spinal reflex. C. Axons of the motor neurons synapse with the interneurons of the spinal cord. D. Axons of the sensory neurons synapse with the interneurons of the spinal cord.arrow_forwardWhich of the following is NOT a reason why a reflex arc is faster than a normal nerve transmission? a. A reflex arc stimulates the motor neurons for an immediate reaction. b. A reflex arc does not send information to the brain to be processed. c. A reflex arc does not involve neurotransmitters. d. A reflex arc involves fewer neurons.arrow_forwardSelect all the true statements a. There are 10 pairs of cranial nerves b. Most of the cranial nerves arise from the brainstem c. Each spinal nerve has motor and sensory fibers d. Each cranial nerve has motor and sensory fibers e. Afferent pathways convey information from the brain to the periphery f. Efferent pathways carry signals from the CNS to muscles and glands g. Afferent spinal nerve fibers leave the spinal cord via the dorsal root h. Efferent spinal nerve fibers leave the spinal cord via the ventral rootarrow_forward
- ILLUSTRATE the following and give their function: A. Cross Section of a Nerve B. Cross Section of the Spinal Cord C. Neuron and Neuroglia in Nerve smear NMN mmnarrow_forwardAmong the followings which does not indicate the stimulation of parasympathetic system? A. Contriction of skeletal muscle blood and vasodilation of renla blood B. Excitation of the blood flow to the kidneys and smooth muscles of Gl tract C. Inhibition of heart rate and amooth muscles of the urinary bladder Excitation of the smooth muscles of the urinary bladder and Gl tractarrow_forwardThe motor system is organized differently in the spiral cord compared to the cortex. Choose the statement below that best describes the difference. a. Alpha motor neurons in the ventral horn are mapped according to muscle location, while cortical motor neurons are organized into purposeful movement groups. b. None of the answers. c. Alpha motor neurons in the ventral horn have a different segment-to-segment organization, while cortical motor neurons are mapped similarly to the somatosensory system. d. Alpha motor neurons in the ventral horn do not have a clear organization, while cortical motor neurons are mapped according to muscle location. e. Alpha motor neurons in the ventral horn are organized into complex movement groups, while cortical motor neurons have no clear organization.arrow_forward
- Study the diagram of a synapse between a sensory neuron and a motor neuron in a simple reflex arc involving only two neurons. Use the information provided by the diagram to answer the questions. 60 mV 2- +40 mv 3. d. -60 mV + 40 mV f 1. If the neurotransmitter substance was acetylcholine, describe two places where this synapse might be found in the body. Answer: From the diagram, identify where receptors for the neurotransmitter would be located. Explain your answer. 2. Answer: 3. Which letter indicates the axon of the sensory neuron? Justify your answer. Answer: 4. Identify where an action potential is occurring. Justify your answer. Answer: What structure is represented by the letter F? What is the function of F? What effect does F have on the transmission of action potentials along the neuron? 5.arrow_forwardDescribe the function of the following types of neurons a. Sensory neurons (also known as ____________ neurons): b. Motor neurons (also known as ____________ neurons): c. Interneurons (also known as ____________ neurons):arrow_forwardPlease note these are all one question group and should be answered as such! Which of the following statements accurately defines epineurium? A. Fluid-filled space at a synapse through which neurotransmitters diffuse B. A vesicle containing neurotransmitters in the axon terminal of a neuron C. The CT sheath that binds together the groups of fascicles, blood vessels, and lymphatic vessels in a peripheral nerve D. The branch of the ANS that adapts the body for rest and digestion Which of the following statements accurately defines sacral plexus? A. The ventral rami of C1–C4 (and a small contribution from C5) that serve the head and neck B. The ventral rami of L1–L4 that serve the pelvis and lower limb C. The ventral rami of C5–T1 that serve the upper limb D. The ventral rami of L4–S4 that serve the pelvis and lower limbarrow_forward
- Hyporeflexia occurs when normal reflexes are weak but not absent. Damage to which of the following would result in hyporeflexia? Hyporeflexia occurs when normal reflexes are weak but not absent. Damage to which of the following would result in hyporeflexia? A.Motor neuron B. Sensory neuron C.Skeletal muscle D. Any of the choices would result in hyporeflexia. Which option to select..arrow_forwardChoose from the word bank below to complete the following statements. a. sensory neurons b. cell body c. Schwann cell d. axon e. motor neurons f. sodium g. processing neurons/interneurons h. effectors i. glial cell j. childbirth/Blood clotting k. potassium 1. action potential m. dendrite n. thermoregulation o. resting potential (81) are the types of neurons responsible for detecting a stimulus in a reflex arc. In a reflex arc (82) are the types of neurons responsible for processing information from a stimulus and deciding how to respond. (83) are the types of neurons responsible for sending out signals to muscles in a reflex arc. In homeostasis, there are sensors, control centres, and (84). (85) is an example of a negative feedback system in homeostasis. (86) is an example of a positive feedback system in homeostasis. A (87) cell nourishes and supports a nerve cell. An example of such a cell is a (88). The three main parts of a neuron are the (89), (90), and the (91). The two main ions…arrow_forwardName the following parts of the neuron as indicated. Specify the functions of each part. 1 7 2 5 4 3 Illustrate and explain the reflex arc. Illustrate and explain transmission of neuronal impulses across synapse.arrow_forward
