A&P 1 Chapter 14 (Lecture) [The Autonomic Nervous System, Part 1] Flashcards
Two Divisions of the Autonomic Nervous System
- Symapthetic
- Parasympathetic
Sympathetic NS
- Fight or Flight
- Prepares body for increased activity
Parasympathetic NS
- Rest and Digest
- Dominant under resting conditions
Effects of Sympathetic NS
Increases
- Metabolic Rate
- Alertness
- Respiratory Rate
- Heart Rate
- Blood Pressure
- Sweating
- Use of energy resources
Decreases
- Digestive system functions
- Urinary system functions
Effects of Parasympathetic NS
Decreases
- Metabolic Rate
- Alertness
- Respiratory Rate
- Heart Rate
- Blood Pressure
- Sweating
Increases
- Digestive system functions
- Urinary system functions
- Storage of energy reserves
Acetylcholine
Cholinergic Receptors (Found in both S & PS)
- Nicotinic Receptors (excitatory)
- Muscarinic Receptors (excitatiry or inhibitory)
Norepinephrine
Adrenergic Receptor (Found in S)
- Alpha (1 & 2)
- Beta (1, 2, & 3)
Alpha 1
Increases contraction of smooth muscle
(Excitatory)
Alpha 2
Decreases contraction of smooth muscle
(Inhibitory)
Beta 1
Stimulates Heart Rate
(Excitatory)
Beta 2
Causes a dilation of airways.
(Inhibitory)
Beta 3
Release of fatty acids from adipose tissue
(Excitatory)
The Two Divisions of the Motor Nervous System
- Somatic NS
- Autonomic NS
Somatic NS
Voluntary Motion (Skeletal Muscles)
Autonomic NS
Involuntary Motion (Cardiac Muscle, Smooth Muscle, & Glands)
Sympathetic Arrangement
- Fibers originate in the thoracolumbar region
- Preganglionic axons short
- Ganglionic axons long
- Ganglia located close to spinal cord
- Preganglionic axons are myelinated & Ganglionic axons are not
Parasympathetic Arrangement
- Fibers originate in the brain and sacral spinal nerves (Craniosacral)
- Preganglionic axons long
- Ganglionic axons short
- Ganglia located in visceral effector organ
- Preganglionic axons are myelinated & Ganglionic axons are not
The region of the brain that regulates the ANS
Hypothalamus
Cerebral Cortex (ANS Interaction)
Communication at subconscious level
Limbic System (ANS Interaction)
Emotions, memory, & behavior
Thalamus (ANS Interaction)
Relay of sensory info
Hypothalamus (ANS Interaction)
Sympathetic & Parasympathetic headquarters
Pons (ANS Interaction)
Higher levels of respiratory control
Medulla Oblongata (ANS Interaction)
Processing centers for complex visceral reflexes (S & P)
Includes:
- Cardiac Centers
- Vasomotor Centers
- Swallowing Center
- Coughing Center
- Respiratory Centers
Spinal Cord T1-L2 (ANS Interaction)
Neurons controlling sympathetic visceral reflexes
Sacral Spinal Cord S2-S4 (ANS Interaction)
Neurons controlling parasympathetic visceral reflexes (such as defecation and urination)
