Question

The autonomic nervous system ________?

1) cannot be self-controlled
2) has one primary division
3) is not affected by drugs
4) is directly controlled by the reticular formation of the brain stem

Answer 1

The autonomic nervous system has two subdivisions, the sympathetic and parasympathetic divisions, which work together to maintain homeostasis and are regulated by the brain stem, including the reticular formation. It is also affected by drugs.

Step-by-step explanation:

The autonomic nervous system is a division of the peripheral nervous system that controls involuntary activities of internal organs and glands, and operates largely outside the realm of voluntary control. It has two primary subdivisions: the sympathetic division, which prepares the body for stress-related activities; and the parasympathetic division, which aids in returning the body to routine operations and is responsible for 'rest and digest' activities. These systems often have opposing effects but work together to maintain the body's homeostasis.

While the autonomic nervous system is not directly controlled by conscious thought, it is linked to and regulated by the brain, notably through centers in the brain stem such as the medulla. The reticular formation of the brain stem and other related structures have descending control over the autonomic system. Moreover, the autonomic system is susceptible to various substances and can be affected by a number of drugs that either mimic or interfere with the neurotransmitters and receptors involved in autonomic responses.