Chapter 4 Flashcards
What is the developing ventral and dorsal horn?
The developing ventral horn is called the basal plate and the dorsal horn is called the alar plate,
What fibres does the ventral and dorsal root carry?
The dorsal roots carry sensory fibres and ventral roots carry motor fibres.
What is the difference between the nerves that emerge from the brainstem and the spinal cord?
The spinal cord nerves contains both components- motor and sensory. Meanwhile, the cranial nerves sometimes are both sensory and motor, only sensory or only motor.
What is the somatic autonomic system?
The somatic system controls the voluntary muscles and receives sensations from the skin.
What is the autonomic nervous system?
The autonomic nervous system controls the visceral organs, blood vessel and receives visceral sensations.
What is sympathetic and parasympathetic system?
They both are part of the autonomic motor system. The parasympathetic nervous system is responsible for controlling the visceral organs for maintains and doing normal processes. The sympathetic nervous system is responsible for the body to ready up for a flight or fight response.
Where is the visceral motor and visceral sensory found in the spinal cord?
The visceral parts are located to medial to the somatic part.
What are the remnants of the gills in humans?
The first arch forms the jaw and the chewing muscles. The second arch forms the muscles of the facial expressions and the bone at the base of the tongue(hyoid bone). The arches 3-6 forms the bones and muscles of the pharynx and larynx.
What refers to the term somatic?
Somatic is a term referring to the skin, muscles and skeleton.
What does the term visceral refer to?
Internal organs, blood vessels, and glands.
How many spinal nerves are there?
8 cervical, 12 thoracic, 5 lumbar, 5 sacral and 1 coccygeal.
How long does the spinal cord extend to
The spinal cord only extends to L1-L2 because the vertebral column grows faster than the spinal cord.
What does the spinal cord form below L1 or L2?
A bundle of the remaining nerve fibres and the meninges called the cauda equina
How many rootlets form the dorsal and ventral roots?
Around 6-12
Who discovered that the ventral roots carried motor fibres and the dorsal roots carried the sensory fibres?
Magendie discovered this almost 200 years ago.
How does the spinal nerve travel?
It exits through the foramina and follow along the rib and supplies the overlying skin and muscles.
What is the area of skin supplied by a single spinal nerve called?
A dermatome.
How was dermatomes studied and mapped?
By the inspection of 100 or more patients with shingles or herpes zoster as these viruses only affects a single dorsal root ganglion. Therefore, painful vesicles appear in only a single dermatome.
Why are dermatome maps useful?
Dermatome maps are useful to determine the location of the pathology and to determine which nerve(s) is or are affected.