Mitochondria and Apoptosis

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I remember this random fact from one of my classes, and it came up on the AAMC FL #1. I understand why C and D are incorrect; D is nonsense because STN is the drug they give to bind to one of the proteins in the activation pathway
C is wrong because the final products; IL-6 and IL-10 cause cell proliferation (cancer, in this case), so a mutation in the genes would inhibit the ability to cause cancer

I guess B is correct because the final member of the pathway (p65/cRel) acts as a transcription factor, binding to DNA at the promoter for the interleukin proteins and causing transcription of their mRNA.

However, in the passage, it says that activation of this pathway leads to inhibition of apoptosis. Mitochondria are involved in promoting apoptosis; therefore, A makes sense. This paper confirms the role of mitochondria in apoptosis
The Role of Mitochondria in Apoptosis


In their explanation, "Mitochondrial disruption would occur if the apoptotic machinery was stimulated, but these genes are anti-apoptotic."

They are suggesting that disruption of the mitochondria causes the mitochondria to activate apoptosis. However, don't mitochondria initiate apoptosis, and the disruption of their function would thus inhibit the cell's ability to initiate apoptosis?

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Where in the passage does it mention that mitochondria stimulates apoptosis? Is it further down in the passage but not posted? While some questions require knowledge outside the passage, based on what you posted, the answer they are looking for can be extrapolated from the passage so don't use outside knowledge. Since B mentions p65/cRel and you see sites for that in the nuclear membrane, and this is found in the passage, I would have chosen that. Sometimes it's better to keep it simple...
 
Where in the passage does it mention that mitochondria stimulates apoptosis? Is it further down in the passage but not posted? While some questions require knowledge outside the passage, based on what you posted, the answer they are looking for can be extrapolated from the passage so don't use outside knowledge. Since B mentions p65/cRel and you see sites for that in the nuclear membrane, and this is found in the passage, I would have chosen that. Sometimes it's better to keep it simple...

It doesn't say that from the passage, but I knew that from what I learned in one of my classes
 
Where in the passage does it mention that mitochondria stimulates apoptosis? Is it further down in the passage but not posted? While some questions require knowledge outside the passage, based on what you posted, the answer they are looking for can be extrapolated from the passage so don't use outside knowledge. Since B mentions p65/cRel and you see sites for that in the nuclear membrane, and this is found in the passage, I would have chosen that. Sometimes it's better to keep it simple...


:(. I actually had B selected at first (because I had no clue), but I marked the question and came back at the end. Then I had a moment where I remembered that fact about mitochondria :(

A made more sense to me than B
 
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Was that last little tidbit in my post above where my reasoning went wrong?
Is it that disruption of mitochondria leads to apoptosis, while normal healthy mitochondria do not activate apoptosis?

Rather than my reasoning, where normal mitochondria functioning causes apoptosis, and their disruption leading to failure of this apoptosis inducing ability?
 
It doesn't say that from the passage, but I knew that from what I learned in one of my classes
Ha. There you go. Unless you are recalling a formula or something high yield that should be known by the majority of test takers (like a major topic in EK), they are not going to expect you to know that mitochondria stimulates apoptosis. Just remember most answers can be found in the passage, if it seems that easy, it is probably easy! These are freebie points so don't second guess!
 
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Was that last little tidbit in my post above where my reasoning went wrong?
Is it that disruption of mitochondria leads to apoptosis, while normal healthy mitochondria do not activate apoptosis?

Rather than my reasoning, where normal mitochondria functioning causes apoptosis, and their disruption leading to failure of this apoptosis inducing ability?
While your reasoning may be correct, I think you are overthinking things. i didn't even know that fact about mitochondria, so if it was me, I would have narrowed it down to A or B. However, B would be more reasonable and within the scope of the passage.
 
While your reasoning may be correct, I think you are overthinking things. i didn't even know that fact about mitochondria, so if it was me, I would have narrowed it down to A or B. However, B would be more reasonable and within the scope of the passage.
Thank you! I hope this doesn't happen to me on the real mcat. I'd like to know if my reasoning is incorrect, but I don't want to get something wrong for a reason like that....I just don't see why A is wrong
 
Thank you! I hope this doesn't happen to me on the real mcat. I'd like to know if my reasoning is incorrect, but I don't want to get something wrong for a reason like that....I just don't see why A is wrong
Ask yourself: it may be a correct answer, but is it the best answer? Would any one else be able to deduce that answer based on the passage? Probably not as it requires specific outside knowledge. Remember, more than half the battle for the mcat is critical thinking/deduction/test taking skills. Your attention is better directed on addressing why you second guessed yourself ie brought in extraneous material when the answer was in the passage and mitochondria was not mentioned anywhere.
 
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Ask yourself: it may be a correct answer, but is it the best answer? Would any one else be able to deduce that answer based on the passage? Probably not as it requires specific outside knowledge. Remember, more than half the battle for the mcat is critical thinking/deduction/test taking skills. Your attention is better directed on addressing why you second guessed yourself ie brought in extraneous material when the answer was in the passage and mitochondria was not mentioned anywhere.
True
Actually, I didn't understand why B was correct until I looked at the question during review. I initially just guessed that.

But B is based on a more general concept
 
Also, since uncontrolled activation leads to uncontrolled cell proliferation, mitochondria wouldn't be disrupted; the cancer cells would need vasts amount of energy to keep proliferating so mitochondria need to be intact and functional...is that what you were looking for? Sorry it is late and I just realized what you were finally asking...that's why A is wrong.
 
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Also, since uncontrolled activation leads to uncontrolled cell proliferation, mitochondria wouldn't be disrupted; the cancer cells would need vasts amount of energy to keep proliferating so mitochondria need to be intact and functional...is that what you were looking for? Sorry it is late and I just realized what you were finally asking...
ah yeah that's true...So that's two competing functions then, right? I found this
Mitochondrial apoptosis-induced channel - Wikipedia

In the face of apoptotic stimuli, mitochondria do indeed cause apoptosis, so it would make sense from what they said in this passage that the interleukin proteins activated cause damage to the mitochondria in order to suppress apoptosis

However, you also have a good point. The cell would need to be able to carry out the Kreb's cycle and ETC/ATP synthesis in order to provide energy for cell proliferation
 
You're reading way too much into this. It sounds like it's just asking about the function of transcription factors and what they do in the promoter region.
 
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