Concept explainers
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.
Want to see the full answer?
Check out a sample textbook solutionChapter 13 Solutions
Human Anatomy & Physiology
- Fill in the blanks below using the following words: Sensory, motor, mixed, muscle, and spinal cord. (Use the image attached to help!!) When the hammer/mallet strikes the patellar tendon, the ______ fibres stretch and stimulate the ______ neurons within those fibres. A nerve impulse is generated and travels from the _____ nerve in the ______ to the ______. The _____ neuron stimulates a _______ neuron within the ______. The _____ neuron sends a nerve impulse back to the ______ causing it to contract which causes the leg to kick.arrow_forwardFill in the blanks Each spinal nerve has a tree-like branching pattern that begins with two “roots”, a (1) ____ with a ganglion, and a (2)____ without a ganglion. Both roots merge to form the (3) ____ itself, which is named based on the vertebra it is associated with (for example, T1 for the first thoracic vertebra or L2 for the second lumbar vertebra). The spinal nerve then splits into three “branches”, the (4) ____ , which carries neurons to and from the back, the (5) ____ , which carries neurons to and from the body wall and limbs, and the (6)____ , which carries neurons to and from internal organs. Each ramus continues to split into additional branches that are given unique names, and these branches may form interwoven networks called (7)____.arrow_forwardComplete transection of the spinal cord produces all of the following effects, except :-a- permanent loss of all sensations mediated by the cord below level of lesionb- permanent loss of voluntary movements by muscles innervated by the cord below level of lesionc- permanent loss of reflexes mediated by the cord below level of lesiond- temporary loss of micturition reflexesarrow_forward
- A typical spinal nerve: Select one: a. normally divides into four branches that will supply the thoracic region, the abdominal region, the pelvic region and the limbs b. is covered by the connective tissue called epineurium c. attaches to the spinal cord via the dorsal root ganglia d. is protected by the dura, arachnoid and pia mater e. contains one nerve fibre and it's myelin sheatharrow_forwardFill in the blank: Each of the thirty-one segments of the spinal cord gives rise to a pair of _______________________.arrow_forwardIn patients with spinal cord injury, neurogenic shock occurs with injury to which of the following spinal cord regions. Select all that apply: Sacral spinal cord C5-C8 spinal cord L4-5 spinal cord T7-T12 spinal cord T1-T6 spinal cord C1-4 spinal cord L1-L3 spinal cordarrow_forward
- A patient presents with paralysis of the right side of the body. A) You know that this patient has suffered brain damage. Explain how you know the damage is to the brain, not the spinal cord. B) What region of the brain is most likely affected? Explain your answer.arrow_forwardAs with most spinal nerves, the sacral spinal nerves become part of a nerve plexus, the sacral plexus. What is a nerve plexus? dermatome maps explain sensory supply, and this patient did not have any motor problems. So which root(s) of nerves were affected, dorsal or ventral? Explain your answer.arrow_forwardSpinal Cord It had been a busy week for Amanda. She had taken three exams, and as if that wasn't stressful enough, her sister was ill and Amanda had to spend much of her time helping out at home. By the end of the week, Amanda decided to go to the beach for a walk and some genuine relaxation. The day was warm and Amanda took off her shoes so she could walk barefoot and feel the sand between her toes. Halfway down the beach, she stepped on something extremely sharp and withdrew her foot in pain. As Amanda hopped around the sand on one foot, rubbing the other to ease the pain, she decided to put her shoes back on. As Amanda stepped on something sharp, she withdrew her foot due to reflexes. Any pain experienced would have been just AFTER she moved her foot off of the sharp object. Why is there a delay in perceiving the pain sensation?arrow_forward
- Spinal Cord It had been a busy week for Amanda. She had taken three exams, and as if that wasn't stressful enough, her sister was ill and Amanda had to spend much of her time helping out at home. By the end of the week, Amanda decided to go to the beach for a walk and some genuine relaxation. The day was warm and Amanda took off her shoes so she could walk barefoot and feel the sand between her toes. Halfway down the beach, she stepped on something extremely sharp and withdrew her foot in pain. As Amanda hopped around the sand on one foot, rubbing the other to ease the pain, she decided to put her shoes back on. Regarding the reflex that moved her injured foot, classify it according to the complexity of the circuit.arrow_forwardAll of the following are functions of the spinal cord except A) mediates quick and involuntary response to a stimuli B) helps maintain posture and equilibrium during locomotion C) receives sensory input and sends motor signals through spinal nerves D) the only control center for parasympathetic nervous systemarrow_forwardCompare and contrast the anterior and posterior rami of a spinal nerve.arrow_forward
- Human Physiology: From Cells to Systems (MindTap ...BiologyISBN:9781285866932Author:Lauralee SherwoodPublisher:Cengage LearningConcepts of BiologyBiologyISBN:9781938168116Author:Samantha Fowler, Rebecca Roush, James WisePublisher:OpenStax College