Question

 Spinal Cord and Spinal Nerves.

86. In an adult, the spinal cord extends from the cervical to the lumbar region.

 a. true

 b. false (the spinal cord extends the entire length of the spinal column to the coccyx) 

87. The lower tip of the spinal cord is the

 a. gray commisure b. white commisure c. denticulate ligament

 d. conus medularis e. spinothalamic tract

 88. The "cauda equina" (horse's tail) is

 a. a sheath of connective tissue which attaches the spinal cord to the skull

 b. an extension of pia mater which attaches the spinal cord to the coccyx

 c. a space between each vertebrae through which the spinal nerves exit

 d. a column of gray matter extending from the spinal cord to the medulla

 e. a group of spinal nerves which extends down from the end of the spinal cord

 89. Which of the above is the filium terminale?

 90. The coverings surrounding the outside of the spinal cord are the

 a. meninges b. endoneurium c. sulci d. fascicles e. tracts

Answer 1

Answer:

Answer 86. Option A; True

Explanation: Spinal cord is a component of the central nervous system which runs dorsally in the human body and remains lodged inside the vertebral column. In adult humans, the total length of the spinal cord is nearly 41 cm. In humans, the spinal cord starts immediately from the end of the medulla oblongata and it terminates at the level of 1^st or 2^nd lumbar vertebrae

Answer 87. Option C; Conus medullaris

Explanation: The spinal cord is known to have an approximate length of nearly 41 cm and it is known to get terminated at the level of 1^st or 2^nd lumbar in the form of a cone like structure called as conus medullaris

Answer 88. Option E; a group of spinal nerves which extends down from the end of the spinal cord

Explanation: Cauda equine refers to the group of the spinal nerves which originates from the conus medullaris. They are called so because of the resemblance of their nerves to that of the horse’s tail

Answer 89. Option B; an extension of the pia mater which attaches the spinal cord to the coccyx

Explanation: The spinal column remains packed inside the vertebral column also called as the back bone. Since the spinal cord terminates at the level of the second lumbar and the vertebral column continues till the level of the coccyx; from the conus medullaris arises a group of fibrous tissue strand which also are the modifications of the pia mater and they are meant to provide support to the spinal cord to be retained within the vertebral column

Answer 90. Option A; meninges

Explanation: Meninges are the protective covering to the spinal cord. They cover the spinal cord from the outside vertebral canal within which they remain located. However also the three protective layers namely the outermost duramater, middlemost arachnoid space, and the innermost piamater are also found in the spinal cord.