Anatomy Homework #6

All spinal nerves contain both sensory and motor axons and are therefore called mixed nerves.

True

Which of the following is a correct pathway for a reflex arc?

sensory receptor → sensory neuron → integrating center → motor neuron → effector

Which of the following would the autonomic nervous system not control?

skeletal muscle

The white and gray rami communicantes are found in which division(s)?

sympathetic

The junction of one neuron to another neuron is called a _________________?

synapse

There are _____ pairs of spinal nerves, consisting of the following groups: _____ pairs of cervical, _____ pairs of thoracic, _____ pairs of lumbar, _____ pairs of sacral, and _____ pair of coccygeal spinal nerves.

31, 8, 12, 5, 5, 1

White rami are associated only with thoracic spinal nerves and the first two or three lumbar spinal nerves. Gray rami are associated with all 31 pairs of spinal nerves.

Both statements are true.

Afferent information is carried in (select letter from diagram below).

E

The myelination of neurons in the PNS is done by __________________?

Schwann cell or neurolemmocyte

In the figure shown, which principal branch of a spinal nerve is indicated? HINT: Axons from this structure form plexuses

anterior (ventral) ramus

The structure shown with the arrow marker is the ________________.

anterior rootlet

How does an autonomic reflex arc differ from a somatic reflex arc?

autonomic reflex arcs contain two motor neurons; somatic reflex arcs contain one motor neuron

Why is the sympathetic division called the thoracolumbar division even though its ganglia extend from the cervical region to the sacral region?

because the cell bodies of preganglionic sympathetic neurons are in the thoracic and lumbar segments of the spinal cord

Why are spinal nerves classified as mixed nerves?

because they contain both motor and sensory neurons

Which of the following are shared anatomical features of the autonomic motor pathways.

both divisions consist of two motor neurons from the CNS to the effector

What does a posterior (dorsal) root ganglion contain?

cell bodies of sensory neurons

The outside connective tissue covering of a spinal nerve is called the _____________.

epineurium

The coverings of a spinal nerve from the most superficial to deep include

epineurium, perineurium, endoneurium

The sympathetic division of the autonomic nervous system (ANS) is often referred to as the _______________________.

flight-or-fight division

The enteric division of the ANS is found in the __________ of the body.

gastrointestinal tract

The sympathetic chain of ganglia are found in this location:

in a vertical row next to the vertebral column

The anterior (ventral) rootlets carry ___________ impulses to the spinal nerves.

motor

Axons and dendrites that are surrounded by a multilayered coating of lipid and protein are said to be _________________?

myelinated

What is/are the "rest and digest" division(s) called?

parasympathetic

Which of the following contains sensory information ONLY?

posterior (dorsal) root

Which of the following contain cell bodies of sensory neurons?

posterior (dorsal) root ganglia

Almost all spinal reflexes are ______________ in their function.

protective

The structure(s) indicated by the lines is/are the _____

rami communicantes

How is a spinal nerve connected to the spinal cord?

rootlets

In the figure shown, what structure is indicated? HINT: This structure contains myelinated axons.

white ramus communicans