Chapter 15: Autonomic NS Flashcards

Study Notes

Nervous System Divisions

The nervous system is divided into CENTRAL and PERIPHERAL.
Central nervous system includes the brain and spinal cord.
Peripheral nervous system is further split into Sensory (visceral and somatic) and Motor (ANS and somatic motor).

Homeostasis Concepts

Walter Cannon coined the terms "homeostasis" and "fight-or-flight."

Autonomic Nervous System (ANS) Overview

The ANS is responsible for regulating fundamental life processes like heart rate, blood pressure, and body temperature.
It controls glands, smooth muscle, and cardiac muscle.

Primary Organs of the ANS

The primary organs include viscera of the thoracic and abdominal cavities.
Also includes structures in the body wall, such as sweat glands and piloerector muscles.

Visceral vs. Somatic Reflexes

Visceral reflexes operate slower than somatic reflexes and involve visceral effectors.

Components of the Visceral Reflex Arc

Receptors detect various internal stimuli such as stretch, tissue damage, and temperature.
Afferent neurons transmit signals to the CNS.
Interneurons are located in the CNS.
Efferent neurons carry signals away from the CNS to effectors that make adjustments.

Example of a Visceral Reflex: Baroreflex

High blood pressure triggers arterial stretch receptors.
Afferent neurons send signals to the CNS.
Efferent signals act on the heart to slow it down, reducing blood pressure.
This process exemplifies a homeostatic negative feedback loop.

Divisions of the Autonomic Nervous System

The SYMPATHETIC division triggers the "fight or flight" response, increasing heart rate, blood pressure, airflow, and blood glucose levels while redirecting blood flow away from the skin and digestive tract.
The PARASYMPATHETIC division facilitates "resting and digesting," lowering energy expenditure and promoting digestion and waste elimination.

Roles of ANS Tone

Parasympathetic tone maintains smooth muscle activity in the intestines and regulates a resting heart rate.
Sympathetic tone helps maintain blood pressure and ensures partial constriction of most blood vessels.

Autonomic Pathway Structure

The autonomic pathway consists of two neurons that communicate at an autonomic ganglion.
The signal must traverse a synapse where the two neurons meet before reaching the target organ.

Description

Test your knowledge of the autonomic nervous system and visceral reflexes with these flashcards. Covering key terms, definitions, and contributions from historical figures, this quiz is perfect for students studying neurobiology. Challenge your understanding of nervous system organization and function!