Nervous System: Cranial, Spinal, and Autonomic Functions

Which nerve innervates the heart, lungs, liver, pancreas, esophagus, stomach, small intestine, and upper portion of the large intestine?

The vagus nerve.

What does Cranial nerve I innervate?

The olfactory epithelium.

What is Cranial nerve II?

The optic nerve.

What does each spinal ganglion consist of?

The cell bodies of sensory neurons.

In the autonomic division, what are the first efferent neurons called?

Preganglionic neurons.

In the parasympathetic system, where do first efferent neurons synapse with second efferent neurons?

In terminal ganglia, located near or within the walls of the organs they innervate.

Neurons from which region innervate the eye, structures of the head, and thoracic and abdominal organs?

The cranial region.

Neurons of the parasympathetic system emerge from the brain and which region of the spinal cord?

The sacral region.

What is a primary effect of parasympathetic nerves?

They decrease heart rate.

Which neurotransmitter is released by postganglionic neurons of the sympathetic system?

Norepinephrine.

Which neurotransmitter is released by preganglionic neurons of the sympathetic system?

Acetylcholine.

What are second efferent neurons called?

Postganglionic neurons.

What are the axons called that leave a ganglion of the paravertebral sympathetic ganglion chain?

Sympathetic nerves.

Which branch of the spinal nerve innervates the anterior and lateral body trunk, as well as the limbs?

The ventral branch.

What consists of afferent (sensory) fibers that transmit information from sensory receptors to the spinal cord?

The dorsal root.

What consists of efferent (motor) fibers leaving the spinal cord?

The ventral root.

Which division of the nervous system works automatically to maintain a steady state within the body?

The autonomic division.

What is the largest nerve arising from the lumbar plexus?

The femoral nerve.

Which nerve arises from the cervical plexus and sends impulses to the diaphragm?

The phrenic nerve.

What is the peripheral nervous system composed of?

Sensory receptors, the nerves that link sensory receptors with the central nervous system (CNS), and the nerves that link the CNS with effectors.

What is the function of the sympathetic nervous system?

It prepares the body for 'fight or flight' responses, increasing heart rate and dilating bronchial tubes.

What is the primary role of the somatic nervous system?

It controls voluntary movements of skeletal muscles and transmits sensory information to the central nervous system.

What are adrenergic neurons?

Neurons that release norepinephrine as their primary neurotransmitter.

What part of the nerve supplies the muscles and skin of the posterior part of the body?

The dorsal branch.

Which plexus receives sensory information from the back of the head, neck, shoulders, and upper chest?

The cervical plexus.

Which plexus supplies the lower abdominal wall, buttock, thigh, and genital structures?

The lumbar plexus.

Which nervous system division is most active during periods of calm and physical rest?

The parasympathetic nervous system.

Which nervous system division prepares the body for action and is most active during stressful situations?

The sympathetic nervous system.

The digestive system is primarily under the control of which nervous system division?

The autonomic nervous system.

What type of stimulation increases the heart rate?

Sympathetic stimulation.

What is the main branch of the sacral plexus and the largest nerve in the body?

The sciatic nerve.

What is the primary function of the optic nerve?

It innervates the retina of the eye.

Parasympathetic nerves that emerge from the sacral region form which nerves?

The pelvic nerves.

What are the two main divisions of the peripheral nervous system?

The somatic and autonomic divisions.

Which division of the peripheral nervous system keeps the body in adjustment with the outside world?

The somatic division.

Which nerve innervates the semicircular canals of the inner ear?

The vestibulocochlear nerve.

What components are included in the somatic system?

Sensory receptors that react to external changes, afferent neurons that inform the CNS, and efferent neurons that signal muscles to respond.

Which nerve innervates the teeth?

The trigeminal nerve.

How many pairs of cervical, thoracic, and lumbar spinal nerves are there?

8 pairs of cervical, 12 pairs of thoracic, and 5 pairs of lumbar spinal nerves.

How many total pairs of spinal nerves emerge from the spinal cord?

31 pairs.

Which neurons release the neurotransmitter norepinephrine?

Postganglionic neurons of the sympathetic system.

What are prostaglandins?

A group of about 16 closely related lipids manufactured by many different tissues in the body.

What are target cells?

Specific cells on which hormones act.