P1 m1 r1 r2 m2 p2 p3 t1 7 why is the anion gap

P1.
M1.
R1.
R2.
9. A 20 mL blood sample is taken from a patient
with lactic acidosis. The pH is measured and
found to be below physiological pH. What
must be true of the [OH
−
] of the sample?
10. The patients in the study have developed
lactic acidosis due to hypoxia. The lactate
dehydrogenase reaction is:
The ratio of lactate to pyruvate is 10:1 in cells
of a healthy individual. If the cells of patients
in the study have an average ratio of 20:1,
7. Why is the anion gap generally greater in
patients suffering from lactic acidosis?
which of the following is most likely to also
be true?
8. Typically, serum lactate level is measured to
determine the severity of lactic acidosis. Why
is this not the ideal approach in the experiment
with Hartmann’s solution from the passage?
A. Acid anions other than lactate are also
relevant in causing lactic acidosis.
B. Hypoalbuminemia may be masking the
effects of a heightened lactate concentration.
C. Hartmann’s solution will confound the
measurement of serum lactate.
D. It is not clear whether each patient’s
lactic acidosis is caused by Hartmann’s
solution or exercise.
KAPLAN TIP
Don’t forget to use the whole passage to answer questions, especially Skill
2 questions.

130
Section II MCAT Skills
2.2: MCAT Scientific Reasoning
LESSON 2.2 REVIEW
MCAT Skill 2 Questions
Scientific Reasoning and Problem Solving
Reasoning about scientific principles, theories, and models
Analyzing and evaluating scientific explanations and predictions
To answer these types of questions:
Determine the likely cause or effect of a phenomenon and determine how observations influence scientific
theories or models.
Determine the validity of an explanation of a phenomenon.

400
Chem/Phys 2: Scientific
Reasoning on the MCAT
PASSAGE 1 (QUESTIONS 1–4)
The adult male human body is composed of approximately 60 percent water. The blood (which is
largely water) is packed with various solutes that are carried to all parts of the body. Of these solutes,
salt makes up a significant portion. Sparingly soluble salts are similar to the salt in the blood in that
they are ionic compounds, but they only dissociate somewhat in water. Two scientists developed