BIO Ch.16 ANS - Efferent Pathways

Question 1

ANS Effectors

Answer 1

Cardiac mm (Heart beat)
Smooth mm (contraction)
Glandular Epithelium (secretion)
Adipose/Kidney tissue (metabolism)

Sympathetic “flight” or “fight”
Parasympathetic “breed and feed” or “rest and repair”

Question 2

Sympathetic Pathway

Answer 2

One sympathetic preganglionic neuron can synapse with many postganglionic neurons (farther from effectors = multiple organs)

Sympathetic Chain Ganglia: C2-Coccyx

Neurotransmitter: Norepinephrine
Apposes Parasympathetic impulses

Question 3

Parasympathetic Pathway

Answer 3

Neurons usually innervate one organ (close to effector organ)

Axons found in CN: III (occulomotor), VII (facial), IX (glossopharyngeal), X (vagus- 75%)

Neurotransmitter: ACh

Question 4

Autonomic Centers Pathway

Answer 4

Frontal Lobe/limbic system > hypothalamus > parasympathetic centers (brainstem/sacral segments) or sympathetic centers (thoracolumber segments)

Question 5

Sympathetic Organ Effects

Answer 5

Eye: pupil dilates (iris m)
Trachea/bronchioles: dilates (incr O2)
Adrenal secretions (Epi/Norepi)
Ureters/Bladder: contracts/relaxes 
Genitalia (male): stimulates ejaculation
Genitalia (female): relax uterus 
Blood vessels (skin,organ mucous membrane)
  -  constrict: pool blood towards skeletal m
Blood vessels (skeletal m): dilate (incr O2)
GI: decrease m motility/tone
Heart: incr rate/contractility 
Salivary glands: thick secretions

Question 6

Parasympathetic Organ Effectors

Answer 6

Eye: pupil contracts 
Trachea/bronchioles: constricts (incr secretion)
Ureters/Bladder: relaxes/contracts
Genitalia (male): stimulates erection
GI: incr m motility/tone
Heart: incr rate/contractility 
Salivary glands: watery secretions 
Lacrimal glands: stimulates tears