Unit 5: The nervous and endocrine systems                    1   2   3   4   5

4.2. The autonomic nervous system

It innervates smooth muscle, cardiac muscle and glands.

It is concerned with heart rate, breathing rate, blood pressure, body temperature, and other visceral activities that work together to maintain homeostasis.

It is formed by nerves which come from the medulla, the spinal cord and parts of the hypothalamus.

It is divided into two subsystems which functions are opposite (antagonistic) and complementary.

- Sympathetic nervous system.

  Its function is to activate the organs

  (with the exception of digestive system)

  Its nerves come from the encephalon and the cervical spinal cord.

  Their ganglia form a chain close to vertebral column.

- Parasympathetic nervous system

Its function is to deactivate the organs

(with the exception of the digestive system)

Its nerves come from the thoracic and the lumbar spinal cord.

Their ganglia are close to the organs which it innervates.

4.3. Think about the actions of Autonomic Nervous System.

       Could they be conscious?  Why?

4.4. Listen and indicate if the following sentences related to the

       peripheral nervous system are true or false.