Bio Destroyer 36 and 49

[DividedByZero]

Can someone explain these answers to me?

36 is basically saying that sperm maturaiton happens in the seminiferous tubules but all the texts I have read says it happens in the epididymis. Only spermatogenesis happens in the seminiferious tubules.


49 says that the autonomic nervous system contains only motor neurons. But, again, all the resources I've come across say that the autonomic nervous system has sensory, motor, AND parasympathetic neurons.

Little help, please. DATs in exactly one week!

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[doc3232]

Can someone explain these answers to me?

36 is basically saying that sperm maturaiton happens in the seminiferous tubules but all the texts I have read says it happens in the epididymis. Only spermatogenesis happens in the seminiferious tubules.


49 says that the autonomic nervous system contains only motor neurons. But, again, all the resources I've come across say that the autonomic nervous system has sensory, motor, AND parasympathetic neurons.

Little help, please. DATs in exactly one week!

I agree with what you think in 36 and I think so for 49.
Books can be more than wrong.

Just relax!!!!

GOOD LUCK

 

[Zerconia2921]

Can someone explain these answers to me?

36 is basically saying that sperm maturaiton happens in the seminiferous tubules but all the texts I have read says it happens in the epididymis. Only spermatogenesis happens in the seminiferious tubules.


49 says that the autonomic nervous system contains only motor neurons. But, again, all the resources I've come across say that the autonomic nervous system has sensory, motor, AND parasympathetic neurons.

Little help, please. DATs in exactly one week!

I know for a fact that sperm is stored in the epididymis and produced in the seminiferous 100% positive.

 

[joh020340]

I know for a fact that sperm is stored in the epididymis and produced in the seminiferous 100% positive.

It is PRODUCED in the seminiferous tubules but acquires motility in the epididymis.

 

[bigstix808]

Can someone explain these answers to me?

36 is basically saying that sperm maturaiton happens in the seminiferous tubules but all the texts I have read says it happens in the epididymis. Only spermatogenesis happens in the seminiferious tubules.


49 says that the autonomic nervous system contains only motor neurons. But, again, all the resources I've come across say that the autonomic nervous system has sensory, motor, AND parasympathetic neurons.

Little help, please. DATs in exactly one week!

36)
spermatogenesis (the creation of spermatids) takes place in the seminiferous tubules

spermiogenesis (the first maturation stage of spematids to sperm) takes place in the seminiferous tubules. they are not capable of free movement, nor fertilization at this point.

Upon entering the epididymus, the sperm THEN gain functional maturity (ie: finish developing a functional tail, full development of acrosome, concentrate mitochondria, etc, and are able to freely swim and capable of fertilization)

if i had to pick an answer when asked the question "where to sperm mature?" i would probably put the seminiferous tubules, unless the question was specifically asking about funtional maturity, then i would put epididymus.

for what its worth, that is my 2 cents. this is what i teach my students, and as cited in the text book we use too.


46)
i agree that the ANS encompasses all of what you said (motor, sensory, etc). i can only see a discrepancy with that response only if they were only assuming that all ANS funtion is via efferent pathways - in which destroyer would be correct. both the symp NS and the parasymp NS are comprised of motor neurons (either directly or indirectly). sensory neurons, i'm assuming, are not being associated with the ANS because they must first past throgh the thalymus first and undergo "interpreatation" before a reaction to that stimulus can be sent out (with the exception of reflex archs of course) via the ANS.

 

[eatkabab]

yes I agree about 36 as well, sperm are only made in the seminiferous, they go to the epididymis to mature and for storage. they get reabsorbed in about a month if they aren't "freed."

I actually just checked the book and it says exactly that, sperm mature in the epididymis, you just miss took the question for "all true" instead of only one being true...

as for number 49, I think its just a little confusing as written rather than wrong. if you don't have a little background in nervous systems you won't understand the answer. heres the background you need for this question:

.........................nervous system (NS)
.......................l..............................l
................Central NS................Peripheral NS
...............l.............l................l..................l
...........Brain........Spine......Somatic NS.....Autonomic NS
..........................................l................l.................l
.................................motor sys.....Sympathetic.....Parasympathetic
.................................sensory &
.................................voluntary
.................................movement


so the question was just trying to "refresh" your memory rather than explain everything to you.

a. somatic NS contains both motor and sensory (true)
b. autonomic contains only motor (true)
c. nothing to do with this picture but true
d. nothing to do with this picture but true

the autonomic NS contains only outgoing nerve lines through the parasympathetic and sympathetic systems. the organs these systems control are called "effector organs." and include things such as the heart, stomach, blood vesicles, digestive tract (small and large), iris, genital organs, bladder, salivation glands, trachea, bronchi, kidney... http://upload.wikimedia.org/wikipedia/commons/f/f7/Gray839.png

just a little more information (mostly cuz this is just building my confidence for my coming exam on the 30th):

the parasympathetic gets its name because it begins/exists the central NS from the top of the neck and the bottom of the spine. like "para substitution" its coming from opposite ends... the parasympathetic uses Ach as both the pre and post ganglionic neurotransmitters. all receptors are muscarinic in the parasympathetic.

the sympathetic NS exists from the thorax and lumbar regions I believe. and synapses on the sympathetic ganglionic column OUTSIDE the Central NS. it uses Ach pre synaptic (on the column) and epinephrine/norepinephrine (major/minor) post synaptic (on the effector organs). muscarinic for presynaptic, alpha and beta adrinergic receptors on the effector organs.

norepinephrine/epinephrine is the same as noradrenaline/adrenaline except its called "epinephrine" when its occurring within the nervous system, and "adrenaline" when its occuring as a "hormone like" neurotransmitter in the blood stream. both are the exact same catecholamine (catecholeamines include dopamine and I think hydroxyapamine?). the larger monoamine group includes seritonin (found in mushrooms...)

sorry for the long post, had fun writing...

 

[DividedByZero]

thanks everyone for the replies! especially the last two. those helped a lot... although i'm still having a little bit of trouble fully wrapping my head around the last one. how exactly does a parasympathetic neuron classify as a motor neuron?

if i'm not mistaken, the definition of a sensory neuron is a neuron that senses external stimuli from the environment. the sympathetic nervous system (fight or flight) would do just that, no?

 

[eatkabab]

how exactly does a parasympathetic neuron classify as a motor neuron?

if i'm not mistaken, the definition of a sensory neuron is a neuron that senses external stimuli from the environment. the sympathetic nervous system (fight or flight) would do just that, no?

you're correct about the definition of a sensory neuron.

well look at it this way. what exactly happens during the "fight or flight" response? a lion is chasing you, your heart starts pumping faster, your eyes dilate, your bronchi expand to let in more air, kidneys stop whatever they're doing, digestive tract freezes in order to shunt all energy to muscles, bladder is stimulated to release anything its holding in order to reduce weight and be able to run faster, veins constrict to move blood faster.... (parasympathetic is the exact opposite during times of rest)

the sympathetic nervous system is causing all these things to happen. these things are not any different than you wanting to move your leg and actually moving it. nerves send signals to your leg muscles to move. in the autonomic system, you're survival instinct knows its time to get the _____ outta there, so your sympathetic system does everything in order to make that process as quick and efficient as possible. the difference in the autonomic NS is that its not under your conscious control.

another example:
if you get your heart cut out by that crazy/evil tribal guy in Indiana Jones 3, your sympathetic/parasympathetic NS's aren't gonna be telling you that your heart is missing. no thats the job of the somatic NS.

heres why, if you have no control over the autonomic system, why would it be useful to you if you could sense things through it? you can't do anything about it because the entire NS is not under your conscious control. now if there WAS a nervous system that you COULD consciously control (somatic NS), THAT would be useful to feel stuff through...

so when you're sitting there, on that iron cooking rod thing above the fiery lava pit with your heart sitting in someones hand in front of you, it'd make more sense, from a survival standpoint, to feel it through a NS that you can control so that you could actually maybe do something about it...



[if you haven't seen the movie, it might be useful to replace the whole heart cutout thing with 'touch a hot stove...']

 

[DividedByZero]

yeah... that makes more sense now. i guess from when i took Gross Anatomy it was taught in a manner that there were three types of neurons (sensory, motor, and parasympathetic) but i guess parasympathetic could classify as motor and it causes motor function for glands.

nice example btw.

 

[Streetwolf]

Visceral sensory exists and is all over your body. Just because you can't feel something doesn't mean it isn't there. You will never know when your blood pressure changes and yet when it does your body attempts to correct the problem. This is one example of visceral sensation. Most organs have it too. When you have a stomach ache, visceral sensation is signaling this to you. The only problem is that the nerves synapse right next to somatic nerves in the spinal cord, so you feel that horrible sharper pain in the somatic structures of your body wall at that spinal cord level.

The ANS has motor and sensory components. I don't know why parasympathetic is being thrown in there as a 3rd part. It is under the motor category.

Oh and for the record, sympathetic got named first. People studying it realized that it was responsible for quite an emotional response, so they called it the sympathetic nervous system. When they discovered its counterpart, they figured they'd call it the parasympathetic nervous system.

I do believe you are thinking of their other names - craniosacral and thoracolumbar. The former is the PANS and the latter is the SANS. These names are derived from the origins of the two nervous systems in the spinal cord/brain.

 

[DividedByZero]

The ANS has motor and sensory components.

wait... that was my original thought. but destroyer says that the ANS is only motor which is what prompted the thread to be made.

 

[Streetwolf]

Destroyer is either wrong or they have broken down the nervous system in a different way. I'm getting my info straight from my notes.

 

[eatkabab]

well, I'm not saying streetwolf is wrong, he's probably correct, although I'm not sure if the visceral sensory aspect is a part of the sympathetic/parasympathetic system. also, I'm somewhat confident that the campbell book (the book the DAT is based on) is more along the lines of the destroyer than what might actually be the "absolute truth."

I've learned it both ways, only motor, motor/sensory. the latter was learned in a more response oriented way rather than sensory and motor. as in, the ANS just responds, and its sensory aspect isn't really considered too much. but thats just my education from one or two teachers. they were old guys... they said ner-OWNs rather than neurons...

 

[dentalplan]

Yea, everyone had pretty good comments on here actually.

I think the take home message should be that the ANS doesn't include sensory neurons because sensory neurons are associated with the CNS, which communicate with the PNS (and thus the ANS) through motor neurons. After that, I guess only motor neurons are involved. So once the signal gets to the ANS, the singal is way after the sensory neuron stage, and thus sensory neurons are not involved in an autonomic response. (This is at least the way I think of it for now, and what I have been inferring from Campbell's ..7th ed.)

Speaking of Campbells, I had a question for eatkabab: how do you know the DAT is based on campbell's? Do you know that for a fact, like did someone from ADA tell you that, or....do you just think that the DAT takes stuff highly from campbell's?

 

[eatkabab]

Speaking of Campbells, I had a question for eatkabab: how do you know the DAT is based on campbell's? Do you know that for a fact, like did someone from ADA tell you that, or....do you just think that the DAT takes stuff highly from campbell's?

they tell you on the ADA site...
http://www.ada.org/prof/ed/testing/dat/index.asp

actual file showing references:
http://www.ada.org/prof/ed/testing/dat/dat_reference_texts.pdf

 

[hoss19]

you should read the answer to the #36 a little bit closer....by choosing answer choice C. (Sperm Expulsion:Vas Deferns) and considering that the question is asking which one of the choice is CORRECTLY MATCHED, answer choice B: (Sperm Maturation:S. Tubules) is therefore wrong....hence the answer supports the fact the sperm DO NOT mature in s.tubules (ie they mature in epididymis...

follow?

Can someone explain these answers to me?

36 is basically saying that sperm maturaiton happens in the seminiferous tubules but all the texts I have read says it happens in the epididymis. Only spermatogenesis happens in the seminiferious tubules.


49 says that the autonomic nervous system contains only motor neurons. But, again, all the resources I've come across say that the autonomic nervous system has sensory, motor, AND parasympathetic neurons.

Little help, please. DATs in exactly one week!