Tricky Questions

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AHOT

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Maybe I'm just completely misunderstanding but I've taken a couple of MCAT tests and every time they ask me, for example

"An RIA for antidiuretic hormone (ADH) performed on a healthy person yielded a concentration of 3 pg/mL. If an RIA were performed on a patient suffering from severe blood loss, which of the following ADH concentrations would the RIA most likely yield"

The stuff about RIA is irrelevant. The point is, I'm wondering if this question is asking for the levels of ADH that will cause a person to suffer from severe blood loss or how ADH levels will respond in response to a person having severe blood loss.

Another example would be

"If the pH of blood were to increase to 7.6, what would be the likely outcome?"

So is this question asking what will happen when the body is more basic --> increase in CO2 exhalation
OR
is it asking what will the body do to bring the pH level down to 7.4 (normal body pH level)?? --> decrease in CO2 exhalation

I completely understand these mechanisms but it's difficult to determine what exactly the question is asking and I am always stuck between two choices.

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ADH primarily functions to 1)maintain homeostasis via reabsorption of body water and 2)increase blood pressure via peripheral resistance when BP drops significantly . It can't cause a loss of blood and the question even says the patient is suffering FROM blood loss. Regardless of how, when the body loses a lot of blood it needs to maintain blood pressure so ADH levels will shoot up to restrict blood vessels and your answer is going to be above 3 pg/mL.. It looks like they are just testing your understanding of ADH and the answer should be very obvious if you understand ADH.

The second question is asking for the response to a higher than normal blood pH so your answer should take into account that the blood is already more basic than usual. The two meanings you are debating between technically are the same because the outcome of excessively basic blood IS what the body does to bring the pH back down-slows breathing rate to decrease exhalation of co2. Be careful with your wording because an increase in breathing rate/co2 exhalation *causes* blood to become more basic but a decrease in breathing rate/co2 exhalation happens *when* the body is more basic.
 
ADH primarily functions to 1)maintain homeostasis via reabsorption of body water and 2)increase blood pressure via peripheral resistance when BP drops significantly . It can't cause a loss of blood and the question even says the patient is suffering FROM blood loss. Regardless of how, when the body loses a lot of blood it needs to maintain blood pressure so ADH levels will shoot up to restrict blood vessels and your answer is going to be above 3 pg/mL.. It looks like they are just testing your understanding of ADH and the answer should be very obvious if you understand ADH.

The second question is asking for the response to a higher than normal blood pH so your answer should take into account that the blood is already more basic than usual. The two meanings you are debating between technically are the same because the outcome of excessively basic blood IS what the body does to bring the pH back down-slows breathing rate to decrease exhalation of co2. Be careful with your wording because an increase in breathing rate/co2 exhalation *causes* blood to become more basic but a decrease in breathing rate/co2 exhalation happens *when* the body is more basic.

You're wonderful thank you so much for clearing this up for me!
 
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