BIO 203
BIO 203 EXAM 4 PURDUE
QUESTIONS AND ANSWERS
LATEST UPDATED 2025
explain how the autonomic and somatic nervous systems differ in form and
function - ANSWERANS- Motor nervous system that controls glands, cardiac
and smooth muscle. Involuntary and visceral reflexes/ actions.
explain how the two divisions of the autonomic nervous system differ
in general
function. - ANSWERParasympathetic- Rest and Digest
(calms body)
Sympathetic- Fight or Flight (excites body)
identify the anatomical components and nerve pathways of the
sympathetic and
parasympathetic divisions - ANSWERParasympathetic-
(craniosacral) Long
preganglionic axons, short
postganglionic axons.
Sympathetic- (thoracolumbar) Short preganglionic axons, long
postganglionic axons. (3
pathway
s)
discuss the relationship of the adrenal glands to the sympathetic
nervous system -
ANSWER2
parts:
Adrenal Cortex- secretes steroid hormones, outer
most layer
Adrenal Medulla- (sympathetic ganglion) secretes hormones
epinephrine and
norepinephrine into the
bloodstream
describe the enteric nervous system of the digestive tract and
explain its significance -
ANSWERNervous system of digestive tract. Does not arise at spinal
cord or brainstem
but still innervates smooth muscles and glands of
digestive tract.
name the neurotransmitters employed at different synapses of the ANS -
ANSWERAcetylcholine (ACh)- secreted by all preganglionic neurons in both
BIO 203 EXAM 4 PURDUE QUESTIONS AND ANSWERS LATEST UPDATED 2025
,BIO 203
parasympathetic and sympathetic divisions and postganglionic neurons in
parasympathetic division.
Norepinephrine (NE)- secreted by nearly all postganglionic neurons in
sympathetic
division with exception of sweat glands
(ACh)
name the receptors for these neurotransmitters and explain how they
relate to autonomic effects - ANSWERCholinergic Receptors- any nerve
that secretes ACh 2 types:
-Nicotinic receptors- on all postganglionic neurons, excitatory
-Muscarinic receptors- on all cardiac and smooth muscle, both excite and
inhibit
Adrenergic Receptors- any nerve that secretes NE
2
types:
-Alpha-adrenergic receptors-
Excitatory
-Beta-adrenergic receptors- Inhibitory (except
heart)
explain how the ANS controls many target organs through dual innervation -
ANSWERdual innervation- receives nerve fibers from both parasympathetic
and sympathetic divisions
antagonistic effects- effects are opposite (parasympathetic
constricts pupils;
sympathetic dilates
pupils)
cooperative effects- both divisions work together to produce
unified effect (both
divisions stimulate to cause
salivation)
explain how control is exerted in the absence of dual innervation -
ANSWERUses
sympathetic nerves firing rate (vasomotor tone) to
determine effect.
Ex: blood flow determined by tone of sympathetic nerves
(Strong tone ->
vasoconstriction; Weak tone ->
vasodilation)
identify what parts of the brain influence the autonomic nervous system -
ANSWERCerebral Cortex- anger, fear, anxiety influence ANS through
connection w/limbic system
BIO 203 EXAM 4 PURDUE QUESTIONS AND ANSWERS LATEST UPDATED 2025
, BIO 203
Hypothalamus- visceral motor control center (hunger, thirst, sex)
Midbrain, pons, medulla- cardiac and vasomotor control (salivation,
swallowing, bladder
contro
l)
give examples of spinal cord control over autonomic functions -
ANSWERurination,
defecation, erection,
ejaculation
interpret a normal electrocardiogram to determine heart rate -
ANSWERdistance
between R waves (large peaks) can be used to determine
heart rate.
Trace the nerve routes of the sympathetic and parasympathetic nervous
systems to their target cells in the heart, and explain how each division of
the autonomic nervous system affects heart rate. - ANSWERParasympathetic
(cardioinhibitory):
1.) Signal leaves medulla via vagus nerves
2.) vagus nerves synapse in cardiac plexus
3.) postganglionic nerves interact with SA and VA nodes
Sympathetic (cardioacceleratory):
1.) Signal leaves spinal cord (T1-T4)
2.) Fibers synapse with postganglionic fibers
3.) Fibers pass through cardiac plexus w/out synapsing
4.) Fibers end at SA & VA nodes, aorta, myocardium
define receptor and sense organ - ANSWERReceptor- Structure specialized
to detect
stimul
us
Sense Organ- Nerve tissue surrounded by other tissue that enhances
response to a
certain type of
stimulus
list the four kinds of information obtained from sensory receptors, and
describe how the nervous system encodes each type - ANSWER1.) Intensity-
strength of stimulus, encoded in 3 ways
- as stimulus intensity rises so does firing frequency of sensory nerves
- intense stimuli recruits greater number of neurons to fire
BIO 203 EXAM 4 PURDUE QUESTIONS AND ANSWERS LATEST UPDATED 2025
BIO 203 EXAM 4 PURDUE
QUESTIONS AND ANSWERS
LATEST UPDATED 2025
explain how the autonomic and somatic nervous systems differ in form and
function - ANSWERANS- Motor nervous system that controls glands, cardiac
and smooth muscle. Involuntary and visceral reflexes/ actions.
explain how the two divisions of the autonomic nervous system differ
in general
function. - ANSWERParasympathetic- Rest and Digest
(calms body)
Sympathetic- Fight or Flight (excites body)
identify the anatomical components and nerve pathways of the
sympathetic and
parasympathetic divisions - ANSWERParasympathetic-
(craniosacral) Long
preganglionic axons, short
postganglionic axons.
Sympathetic- (thoracolumbar) Short preganglionic axons, long
postganglionic axons. (3
pathway
s)
discuss the relationship of the adrenal glands to the sympathetic
nervous system -
ANSWER2
parts:
Adrenal Cortex- secretes steroid hormones, outer
most layer
Adrenal Medulla- (sympathetic ganglion) secretes hormones
epinephrine and
norepinephrine into the
bloodstream
describe the enteric nervous system of the digestive tract and
explain its significance -
ANSWERNervous system of digestive tract. Does not arise at spinal
cord or brainstem
but still innervates smooth muscles and glands of
digestive tract.
name the neurotransmitters employed at different synapses of the ANS -
ANSWERAcetylcholine (ACh)- secreted by all preganglionic neurons in both
BIO 203 EXAM 4 PURDUE QUESTIONS AND ANSWERS LATEST UPDATED 2025
,BIO 203
parasympathetic and sympathetic divisions and postganglionic neurons in
parasympathetic division.
Norepinephrine (NE)- secreted by nearly all postganglionic neurons in
sympathetic
division with exception of sweat glands
(ACh)
name the receptors for these neurotransmitters and explain how they
relate to autonomic effects - ANSWERCholinergic Receptors- any nerve
that secretes ACh 2 types:
-Nicotinic receptors- on all postganglionic neurons, excitatory
-Muscarinic receptors- on all cardiac and smooth muscle, both excite and
inhibit
Adrenergic Receptors- any nerve that secretes NE
2
types:
-Alpha-adrenergic receptors-
Excitatory
-Beta-adrenergic receptors- Inhibitory (except
heart)
explain how the ANS controls many target organs through dual innervation -
ANSWERdual innervation- receives nerve fibers from both parasympathetic
and sympathetic divisions
antagonistic effects- effects are opposite (parasympathetic
constricts pupils;
sympathetic dilates
pupils)
cooperative effects- both divisions work together to produce
unified effect (both
divisions stimulate to cause
salivation)
explain how control is exerted in the absence of dual innervation -
ANSWERUses
sympathetic nerves firing rate (vasomotor tone) to
determine effect.
Ex: blood flow determined by tone of sympathetic nerves
(Strong tone ->
vasoconstriction; Weak tone ->
vasodilation)
identify what parts of the brain influence the autonomic nervous system -
ANSWERCerebral Cortex- anger, fear, anxiety influence ANS through
connection w/limbic system
BIO 203 EXAM 4 PURDUE QUESTIONS AND ANSWERS LATEST UPDATED 2025
, BIO 203
Hypothalamus- visceral motor control center (hunger, thirst, sex)
Midbrain, pons, medulla- cardiac and vasomotor control (salivation,
swallowing, bladder
contro
l)
give examples of spinal cord control over autonomic functions -
ANSWERurination,
defecation, erection,
ejaculation
interpret a normal electrocardiogram to determine heart rate -
ANSWERdistance
between R waves (large peaks) can be used to determine
heart rate.
Trace the nerve routes of the sympathetic and parasympathetic nervous
systems to their target cells in the heart, and explain how each division of
the autonomic nervous system affects heart rate. - ANSWERParasympathetic
(cardioinhibitory):
1.) Signal leaves medulla via vagus nerves
2.) vagus nerves synapse in cardiac plexus
3.) postganglionic nerves interact with SA and VA nodes
Sympathetic (cardioacceleratory):
1.) Signal leaves spinal cord (T1-T4)
2.) Fibers synapse with postganglionic fibers
3.) Fibers pass through cardiac plexus w/out synapsing
4.) Fibers end at SA & VA nodes, aorta, myocardium
define receptor and sense organ - ANSWERReceptor- Structure specialized
to detect
stimul
us
Sense Organ- Nerve tissue surrounded by other tissue that enhances
response to a
certain type of
stimulus
list the four kinds of information obtained from sensory receptors, and
describe how the nervous system encodes each type - ANSWER1.) Intensity-
strength of stimulus, encoded in 3 ways
- as stimulus intensity rises so does firing frequency of sensory nerves
- intense stimuli recruits greater number of neurons to fire
BIO 203 EXAM 4 PURDUE QUESTIONS AND ANSWERS LATEST UPDATED 2025
