Introduction to the Autonomic Nervous System Quiz

Answer: Swallowing

The autonomic nervous system is responsible for controlling the involuntary actions of the body, such as digestion, body temperature, and heart rate. It does this by controlling the smooth muscle of the internal organs and glands.

Answer: Peripheral Nervous System

The central nervous system consists of the brain and the spinal cord, and receives messages from parts of the body. It processes these messages and sends signals out to parts of the body.

The peripheral nervous system links the central nervous system to the skin, muscles and other organs. The autonomic nervous system is part of this.

Answer: Intercostal Nerves

Intercostal nerves are the anterior divisions of the rami of thoracic segmental spinal nerves from T1 to T11. They are in the abdomen and run along the subcostal groove of a rib, as well as the intercostal vessels.

The anterior or ventral rami of cervical segmental spinal nerves (C3 to C5) form phrenic nerves.

These nerves are mainly somatic, which supply things like the body wall, joints and the skin. However, segmental spinal nerves also carry some visceral or autonomic afferents and efferents.

Answer: To conserve and restore energy

The parasympathetic division is responsible for conserving and restoring energy. The sympathetic division produces a "fight or flight" response and the effects that are apparent in this situation, such as an increased heart rate.

Answer: 12

Cranial nerves come from the brain stem. Information from the parasympathetic nervous system in the brain stem runs along cranial nerve III, VII, IX or X. From leaving the brain stem, it travels along preganglionic neurones, through the autonomic ganglion, along postganglionic neurones and then to the target organ or tissue.

This is the same in the sacral portion of the spinal cord, but it runs along the pelvic nerve instead.

Answer: X

The vagus nerve is distributed from the head and neck into the thorax and abdomen. It has a wide range of important functions in the body, such as heart rate and sweating.

Answer: Acetylcholine

Acetylcholine is also a neurotransmitter in the central nervous system and peripheral nervous system.

The autonomic nervous system has other neurotransmitters, such as norpinephrine, but acetylcholine is the only one used in the parasympathetic division.

In the sympathetic division, acetylcholine is still used as a neurotransmitter in preganglionic neurones, but norpinephrine is used in postganglionic neurones, apart from sweat glands which use acetylcholine.

Answer: L2

The ganglia in the sympathetic nervous system are more organized than in the parasympathetic nervous system, as all preganglionic fibres run to sympathetic chains.

Answer: Splanchnic Nerves

All splanchnic nerves carry sympathetic fibres except pelvic splanchnic nerves, which carry parasympathetic fibres.

Answer: Phrenic Nerve

Phrenic nerves originate from C3, C4 and C5. Severing of the spinal cord above the origin of the phrenic nerves causes breathing to stop as impulses are no longer sent to the diaphragm.