Acid-Base Balance: The Bicarbonate System and Compensation · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Two organs, one pH

Science · The Human Body · ages 20-22
Name ______________________   Date ____________

  1. Low pH with high carbon dioxide points to which disorder?

    • Metabolic alkalosis
    • Metabolic acidosis
    • Respiratory acidosis

  2. Which two quantities does the bicarbonate buffer link?

    • Carbon dioxide and bicarbonate
    • Oxygen and iron
    • Salt and sugar

  3. The lungs adjust carbon dioxide within minutes while the kidneys tune bicarbonate over days.

    Circle one:   True   False

  4. A respiratory acidosis begins. Which organ compensates and when?

    • The lungs within minutes
    • Neither organ ever
    • The kidneys over hours to days

  5. pH is low and bicarbonate is low while carbon dioxide is also low. What is happening?

    • Respiratory acidosis alone
    • Metabolic acidosis with lung compensation
    • Respiratory alkalosis

  6. pH has returned exactly to 7.4 with both values still shifted. What does that mean?

    • Full compensation finished cleanly
    • The disorder must be brand new
    • A second disorder hides behind the first

  7. Compensation completely erases every trace of the original disturbance.

    Circle one:   True   False

  8. A student sees normal pH and declares the acid base story over. What is the error?

    • Normal pH forbids shifted values
    • A compensated disorder hides behind normal pH with shifted partners
    • Buffers never act in seconds
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Answer key

For grown-ups. Fold this page away before handing over the rest.

Two organs, one pH W1-mt_LFLgZre62C-s1

  1. Respiratory acidosis · Carbon dioxide off first means the start was respiratory, and low pH means acid.
  2. Carbon dioxide and bicarbonate · One reaction joins the lung controlled gas to the kidney controlled ion.
  3. True · Fast air handling beats slow salt handling by far.
  4. The kidneys over hours to days · The partner system answers, and the kidney partner is slow.
  5. Metabolic acidosis with lung compensation · Bicarbonate off first names it metabolic, and low carbon dioxide shows the lungs answering.
  6. A second disorder hides behind the first · Compensation never fully normalizes, so exact return with shifted values means a mixed disorder.
  7. False · It moves pH toward normal without overshooting, so the origin stays readable.
  8. A compensated disorder hides behind normal pH with shifted partners · Pushback can normalize pH while both partners sit shifted.
Worksheet · LightMySky