Week 11: Acid Base Inbalance Flashcards
Exam 4
What is the pH scale described as?
Logarithmic, not linear
Solutions with an excess of hydrogen ions are ____in nature.
acidic
Solutions with an excess of hydroxide ions (OH-) are…
basic or alkaline in nature
What is defined as neutral in biologic fluids?
a pH of 7.40
How do body acids form? What do these body acids release?
Body acids form as the end products of protein, carbohydrate, and fat metabolism; these acids can release hydrogen ion.
Base
A base is a substance that accepts hydrogen ions;
Acid
an acid is a substance that donates hydrogen ions.
Body acids exist as what two forms:
- volatile acids
- nonvolatile acids
volatile acids
(substances that can be eliminated as carbon dioxide [CO2] gas)
nonvolatile acids
(substances that can be eliminated only by the kidney).
What is the sole volatile acid formed in the body?
The sole volatile acid formed in the body is carbonic acid (H2CO3), a weak acid
Weak acid
it does not easily release its hydrogen ion.
Examples of nonvolatile acids:
lactic acid, phosphoric acid, sulfuric acid, acetoacetic acid, and beta-hydroxybutyric acid.
Many nonvolatile acids are considered what?
Strong acids
Strong acids
They readily release their hydrogen ions.
How are nonvolatile acids eliminated/
Nonvolatile acids are secreted into the urine by the renal tubules in amounts of approximately 60 to 100 mEq of hydrogen per day, or about 1 mEq per kilogram of body weight.
The body has three mechanisms, or lines of defense, to maintain the acid–base balance:
(1) physiologic (chemical) buffer systems (bicarbonate, phosphate, hemoglobin, and protein), the first line of defense;
(2) respiratory acid–base control, the second line of defense; and
(3) renal acid–base control, the third line of defense.
Buffer systems
resist changes in pH and maintain pH within the normal range
ECF Plasma buffer system two components:
- carbonic acid bicarbonate
- protein hemoglobin
Most important intracellular buffers:
- phosphate and
- protein
WHat are the most important renal buffers:
- Ammonia
- Phosphate
What is the base component of the carbonic-bicarb buffer system
bicarbonate ion
What is the acid component of the carbonic-bicarb buffer system?
hydrogen ion
What do the lungs do with CO2 and how?
The lungs eliminate CO2 and can increase the amount of CO2 eliminated by increasing the rate and depth of ventilation.