autonomic nervous system question

[DATlongshui]

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Can anyone please clarify the neuron compositions of autonomic nervous system? I did two Qs, one is Kaplans (below) which seems to imply there is only two motor neurons in ANS?
Q: which statement is false: (from kaplan, answer is C)
A.The motor neurons of the sympathetic nervous system originate in the thoracic and lumbar regions of the spinal cord.
B. The sympathetic nervous system regulates the secretion of adrenaline and noradrenaline from the adrenal medulla.
C. The nervous pathways of the autonomic nervous system consist of one sensory neuron and one motor neuron.
D. The motor neurons in the parasympathetic nervous system that originate in the cranial and sacral regions of the spinal cord synapse near the target site.
E. The autonomic nervous system regulates the heart, the smooth muscle in the walls of the digestive tract, the respiratory system and the excretory system.

However, in destroyer Q69 for false statement, B is given as the answer, in which it states: the ANS contains only motor neurons.

I looked at Kaplan BB, which mentioned autonomic innervation of the body includes both sensory and motor fibers. <= is it same as neurons or sth else? Besides, I also looked up online, and seems that ANS contains sensory neurons too.

I am really confused at this point. Can anybody educate me for this? Did I misunderstand some of the wording here? Thanks!

 

[wantVCUdental]

Can anyone please clarify the neuron compositions of autonomic nervous system? I did two Qs, one is Kaplans (below) which seems to imply there is only two motor neurons in ANS?
Q: which statement is false: (from kaplan, answer is C)
A.The motor neurons of the sympathetic nervous system originate in the thoracic and lumbar regions of the spinal cord.
B. The sympathetic nervous system regulates the secretion of adrenaline and noradrenaline from the adrenal medulla.
C. The nervous pathways of the autonomic nervous system consist of one sensory neuron and one motor neuron.
D. The motor neurons in the parasympathetic nervous system that originate in the cranial and sacral regions of the spinal cord synapse near the target site.
E. The autonomic nervous system regulates the heart, the smooth muscle in the walls of the digestive tract, the respiratory system and the excretory system.

However, in destroyer Q69 for false statement, B is given as the answer, in which it states: the ANS contains only motor neurons.

I looked at Kaplan BB, which mentioned autonomic innervation of the body includes both sensory and motor fibers. <= is it same as neurons or sth else? Besides, I also looked up online, and seems that ANS contains sensory neurons too.

I am really confused at this point. Can anybody educate me for this? Did I misunderstand some of the wording here? Thanks!

Yes you misunderstood the wording, in destroyer #69, answer was B.
The question asks "which of the following is false?"
answer: ANS only contains only motor neuron (SO! this would mean... ANS contain MORE than motor neurons! and indeed, the ANS consists of Motor Neurons, Interneurons and Sensory Neurons)

In Kaplan, the answer was C because ANS has more than 1 sensory and motor neuron.

So if you lay out the statements... the concepts overlap but the solutions do not conflict.

 

[jay47]

Can anyone please clarify the neuron compositions of autonomic nervous system? I did two Qs, one is Kaplans (below) which seems to imply there is only two motor neurons in ANS?
Q: which statement is false: (from kaplan, answer is C)
A.The motor neurons of the sympathetic nervous system originate in the thoracic and lumbar regions of the spinal cord.
B. The sympathetic nervous system regulates the secretion of adrenaline and noradrenaline from the adrenal medulla.
C. The nervous pathways of the autonomic nervous system consist of one sensory neuron and one motor neuron.
D. The motor neurons in the parasympathetic nervous system that originate in the cranial and sacral regions of the spinal cord synapse near the target site.
E. The autonomic nervous system regulates the heart, the smooth muscle in the walls of the digestive tract, the respiratory system and the excretory system.

However, in destroyer Q69 for false statement, B is given as the answer, in which it states: the ANS contains only motor neurons.

I looked at Kaplan BB, which mentioned autonomic innervation of the body includes both sensory and motor fibers. <= is it same as neurons or sth else? Besides, I also looked up online, and seems that ANS contains sensory neurons too.

I am really confused at this point. Can anybody educate me for this? Did I misunderstand some of the wording here? Thanks!

Bad question on Kaplan's part, but it is a good concept to understand. Read the question carefully, it says pathways consist of ONE afferent and ONE efferent pathway. While the ANS does have a few afferent pathways, a majority of the pathways are SOLEY efferent. Therefore for most classes it is simply understood that the ANS is efferent/motor. Even my gross professor says this.

, "They are probably limited to the white rami connected with the spinal nerves in two groups, viz., the first thoracic to the second or third lumbar and the second sacral to the fourth sacral nerves" (wiki for General visceral Afferent pathways)

http://en.wikipedia.org/wiki/Primary_visceral_sensory

 

[jay47]

Yes you misunderstood the wording, in destroyer #69, answer was B.
The question asks "which of the following is false?"
answer: ANS only contains only motor neuron (SO! this would mean... ANS contain MORE than motor neurons! and indeed, the ANS consists of Motor Neurons, Interneurons and Sensory Neurons)

In Kaplan, the answer was C because ANS has more than 1 sensory and motor neuron.

So if you lay out the statements... the concepts overlap but the solutions do not conflict.

I disagree with this logic (sorry). It does not literally imply that the ANS is composed of 2 neurons, one sensory and one motor. It is implying that each pathway, of which there are many, is NOT composed of one sensory and one motor. Most pathways are only motor, or rather, most well defined pathways are motor.

Pretty much, just trust the "idea" that the ANS is motor only. For DAT sakes, that's what I would go with.

 

[DATlongshui]

Yes you misunderstood the wording, in destroyer #69, answer was B.
The question asks "which of the following is false?"
answer: ANS only contains only motor neuron (SO! this would mean... ANS contain MORE than motor neurons! and indeed, the ANS consists of Motor Neurons, Interneurons and Sensory Neurons)

In Kaplan, the answer was C because ANS has more than 1 sensory and motor neuron.

So if you lay out the statements... the concepts overlap but the solutions do not conflict.

Thanks for your help. I don't have much of problem with destroyer's question; however, what really confused me is when you add up the two Qs. I should have posted kaplan's answer explanation: Choice C is false because the nervous pathways of the autonomic nervous system consist of two motor neurons, not one sensory neuron and one motor neuron. The first motor neuron in the pathway has its cell body within the central nervous system (CNS), then synapses outside of the CNS with the second motor neuron, which innervates the effector.

Anyway, it is always good to discuss this here, as I seem to have a clearer pic now.

 

[DATlongshui]

I disagree with this logic (sorry). It does not literally imply that the ANS is composed of 2 neurons, one sensory and one motor. It is implying that each pathway, of which there are many, is NOT composed of one sensory and one motor. Most pathways are only motor, or rather, most well defined pathways are motor.

Pretty much, just trust the "idea" that the ANS is motor only. For DAT sakes, that's what I would go with.

Really appreciate the explanation. I think I will go with your interpretation for DAT.

 

[jay47]

Really appreciate the explanation. I think I will go with your interpretation for DAT.

Well, in fact I don't even know that my explanation was 100% clear, because the question is a little "leading". You have to think what they were trying to get you to think, and as the explanation says, each motor pathway (sympathetic and parasympathetic) is actually composed to two motor neurons instead of one motor and one sensory. It's all good though.

 

[sfoksn]

let me get this straight,

so Autonomic nervous system only contains motor neurons for DAT's sake, right?

So why is the destroyer questions choosing the choice "The autonomic nervous system contains only motor neurons" as an answer to a question asking to choose what is false?

Shouldn't that answer choice be eliminated b/c it's true?