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Ch. 17 Blood
Marieb - Human Anatomy & Physiology 11th Edition
Marieb, Hoehn11th EditionHuman Anatomy & PhysiologyISBN: 9780136874034Not the one you use?Change textbook
Chapter 17, Problem 9

The normal pH of the blood is about:
a. 8.4
b. 7.8
c. 7.4
d. 4.7

Verified step by step guidance
1
Understand that blood pH is a measure of how acidic or basic the blood is, with 7 being neutral on the pH scale.
Recall that normal human blood pH is slightly basic, meaning it is just above 7 on the pH scale.
Eliminate options that are too acidic (below 7) or too basic (much higher than normal physiological range).
Recognize that the typical normal blood pH is tightly regulated around 7.4 to maintain proper physiological function.
Conclude that among the given options, the value closest to the normal blood pH is 7.4.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Normal Blood pH Range

The normal pH of human blood is tightly regulated between 7.35 and 7.45, with an average around 7.4. This slightly alkaline range is essential for proper cellular function and metabolic processes.
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Acid-Base Balance

Acid-base balance refers to the mechanisms the body uses to maintain blood pH within the normal range. It involves buffers, respiratory control of CO2, and renal regulation of bicarbonate to prevent acidosis or alkalosis.
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Physiological Importance of pH

Maintaining blood pH near 7.4 is crucial because enzyme activity, oxygen transport, and electrolyte balance depend on it. Deviations can lead to serious health issues like acidosis or alkalosis, affecting organ function.
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