Acid-Base III: Balance

Question 1

The body has 3 primary mechanisms to defend against alterations in ECF pH:

Answer 1

1. EC and IC buffering power
2. Adjusting ventilation properties of lungs to alter PCO2
3. Adjusting RNAE

Question 2

What is the initial response to addition of acid or alkali to the system?

Answer 2

buffer response, with EC buffers acting almost instantaneously and IC buffers acting more slowly with a response time of several minutes

Question 3

What is the main ECF buffer system, and what causes its levels to rise or fall?

Answer 3

bicarbonate buffer system; levels of bicarbonate will either rise or fall depending on whether the pH was acidic (fall) or alkaline (rise)

Question 4

H+ is titrated intracellularly by which 3 things?

Answer 4

bicarbonate, phosphate, and proteins (like imidazole group of Hb)

Question 5

Almost all buffering in respiratory acid-base disorders occurs ________.

Answer 5

intracellularly

Question 6

What are the primary, secondary, and tertiary defenses against insults to acid-base balance in the body?

Answer 6

• primary: buffering capacity (intracellularly and extracellularly)
• secondary: lungs via ventilatory rate
• tertiary: kidneys via adjustments of RNAE

Question 7

If blood pH is within normal range, what is the ratio fo base to acid?

Answer 7

20:1