Autonomic Nervous System

These flashcards cover key concepts regarding the structure and function of the Autonomic Nervous System, including its divisions, pathways, neurotransmitters, and associated disorders.

What is the primary function of the Autonomic Nervous System (ANS)?

Controls involuntary functions such as blood pressure, heart rate, digestive, and urinary functions.

What neurotransmitter is released by preganglionic neurons in the autonomic nervous system?

Acetylcholine (ACh) is released by preganglionic neurons.

What distinguishes somatic efferent innervation from autonomic efferent innervation?

Somatic efferent innervation is voluntary and involves a single neuron pathway, whereas autonomic efferent innervation is involuntary and involves two neurons.

Describe the two divisions of the Autonomic Nervous System.

The sympathetic division, responsible for 'fight or flight' responses, and the parasympathetic division, responsible for 'rest and digest' functions.

Where are the preganglionic neurons for the sympathetic division located?

In the lateral horns of the thoracic spinal cord (T1-L2).

What are the effects of sympathetic stimulation on the heart?

Increased heart rate and force of contraction.

What is the role of the parasympathetic division in the body?

Conservation of energy and promotion of restorative processes.

What type of receptors are associated with parasympathetic postganglionic fibers?

Muscarinic receptors for acetylcholine.

What happens during the 'fight or flight' response?

Increased heart rate, dilated pupils, and increased blood flow to muscles.

What is Horner’s Syndrome?

A disorder characterized by unilateral pupillary constriction, sagging of the eyelid, and flushing of skin due to lesions in the sympathetic division.

What does dual innervation of organs mean?

Antagonistic effects where both sympathetic and parasympathetic divisions control the same organ.

What role does the hypothalamus play in the autonomic nervous system?

Regulates body temperature, hunger, thirst, and sexual response.