In which PO2 environment would hemoglobin most easily release its O2?

Question

A.  75 mm Hg
B.  100 mm Hg
C.  65 mm Hg
D.  90 mm Hg
E.  40 mm Hg

Clarify Question
What is the key concept addressed by the question?
What type of thinking is required?
 
Gather Content
What do you already know about oxygen levels? What other information is related to the question?

Choose Answer
Given what you now know, what information is most likely to produce the correct answer?

Reflect on Process
Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
 

Answer 1

E.  40 mm Hg

Clarify Question
What is the key concept addressed by the question?
        · This question is asking about the environmental influence on the release of oxygen by hemoglobin.
What type of thinking is required?
        · Apply level:
            o You are being asked to take what you already know and use, or apply, it to hemoglobin and its tendency to release oxygen.
 
Gather Content
What do you already know about oxygen levels? What other information is related to the question?
        · Diffusion is the movement of a substance from high to low concentration.
        · As the difference between high and low concentration increases, the rate of diffusion increases.
        · When blood leaves the alveoli, the PO2 is 100mmHg.
        · ThePO2 of the tissues of the body is 40mmHg.

Choose Answer
Given what you now know, what information is most likely to produce the correct answer?
        · Since 40mmHg is the lowest value, it creates the largest concentration gradient, which would facilitate the greatest movement of oxygen.

Reflect on Process
Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
        · Apply level:
            o Answering this question correctly depended on your ability to use the nature of hemoglobin in a new situation. If you got an incorrect answer, did you remember that the PO2 of blood leaving the alveoli is 100mmHg, or that typical cells have a PO2 of 40mmHg? Did you have trouble extending the nature of hemoglobin to determine the correct answer?