TPRH Science Workbook Bio Passage 64

[CaribbeanBlue]

I am having issues with the logic behind #3.

I always thought low glucagon levels indicates higher glucose levels... is this logic false?

Thanks!

This is from 2010 workbook btw.

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[Testosterone]

It is not the only indicator of high glucose levels. Type 1 diabetes is an autoimmune disorder that leads to destruction of beta islet cells responsible for secreting insulin. This leads to lower insulin levels. Insulin is directly responsible for serum glucose uptake and therefore higher glucose levels.

 

[MadRadLad]

lucagon makes glucose "gone" from the cells, and put out into the bloodstream.

If you have low glucagon levels, the glucose is more likely to stay inside the cell rather than entering the bloodstream.

In that particular question, someone with Type 1 Diabetes Mellitus (autoimmune destruction of beta cells) will have low insulin levels. Which means that glucose, rather than being told to enter the cells by insulin, just stays around in the bloodstream. The question states that A1C corresponds with serum glucose levels. Without insulin to allow glucose to go into cells, it will stay in the bloodstream. Thus out of the answer choices, the man with Type 1 Diabetes will have the highest serum glucose concentration, and by extension the highest A1C count.

Note - The sickle cell anemia makes choice D wrong. The question states A1C levels also rely on the RBC life cycle. Sickle cell RBCs don't live as long as normal RBCs.

 

[gettheleadout]

Moving to MCAT Q&A.