The Autonomic Nervous System and the Adrenal Medulla

These flashcards cover the key concepts and information related to the autonomic nervous system and its functions.

What is the primary function of the autonomic nervous system?

To control most visceral functions, such as arterial pressure and gastrointestinal motility.

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

Sympathetic and parasympathetic nervous systems.

Where do sympathetic pre-ganglionic neurons originate?

From T1 to L2 of the spinal cord.

What neurotransmitter is released by sympathetic post-ganglionic neurons?

Norepinephrine.

What neurotransmitter is released by parasympathetic post-ganglionic neurons?

Acetylcholine.

What is the effect of the sympathetic nervous system on the heart rate?

It increases the heart rate.

What is the effect of the parasympathetic nervous system on the heart rate?

It decreases the heart rate.

What is the main function of the adrenal medulla?

To secrete epinephrine and norepinephrine into the blood.

What type of receptor do norepinephrine and epinephrine stimulate predominantly?

Alpha adrenergic receptors.

Which cranial nerves are involved in the parasympathetic nervous system?

Cranial nerves III, VII, IX, and X.

What is the 'fight or flight' response?

The body's reaction to a life-threatening situation characterized by increased heart rate, arterial pressure, and blood flow to muscles.

What type of receptors are nicotinic receptors?

Receptors that respond to acetylcholine and are found at synapses between pre-ganglionic and post-ganglionic neurons.

Where are the sympathetic chain ganglia located?

Adjacent to the spinal cord.

What is the role of acetylcholinesterase?

To break down acetylcholine in the synaptic cleft.

What is the significance of sympathetic tone?

Provides a baseline level of constriction in blood vessels.

What is the role of the hypothalamus in the autonomic nervous system?

It controls various autonomic functions, including temperature regulation and feeding.

What is the location of alpha (α) receptors?

Primarily in blood vessels.

What effect do beta1 receptors have when activated?

They increase heart rate and contractility.

What is the result of parasympathetic stimulation of glands?

Increased secretion from nasal, lacrimal, salivary, and gastrointestinal glands.

What is the impact of sympathetic stimulation on the gastrointestinal tract?

Sympathetic stimulation has very little effect on gastrointestinal activity.

What is the fiber type of the parasympathetic pre-ganglionic neurons?

Cholinergic, meaning they use acetylcholine as a neurotransmitter.

What effect does nicotine have on the autonomic nervous system?

It stimulates both sympathetic and parasympathetic neurons.

What neurotransmitter is primarily involved in sympathetic responses?

Norepinephrine.

How does the autonomic nervous system affect blood vessels?

Sympathetic causes vasoconstriction, while parasympathetic can cause vasodilation.

What is the primary component that regulates visceral functions in the autonomic nervous system?

The central nervous system, particularly the brain and spinal cord.

What is the post-ganglionic fiber type of the parasympathetic nervous system?

Cholinergic, using acetylcholine.

What is the physiological response triggered by the adrenal medulla hormones?

Prolonged activity and increased metabolic rate and cardiovascular function.

What defines the 'alarm' response of the sympathetic nervous system?

A mass discharge of sympathetic activity in response to stress.

What type of activity does the sympathetic nervous system facilitate in skeletal muscles?

Increased blood flow and muscle strength.

What are the two main types of adrenergic receptors?

Alpha and beta adrenergic receptors.

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

It transmits signals to autonomic centers in the brain.

What is the relationship between the autonomic nervous system and the stress response?

The autonomic nervous system coordinates the body's reaction to stress through sympathetic activation.