A&P: Water, Electrolyte, & Acid-Base Balance Flashcards
Describe how water balance is related to electrolyte balance
- Water balance is interdependent to electrolyte balance because H2O follows salt (electrolyte)
-> Ex: increase loss of electrolyte = increase loss of H2O
Define: Acid-Base Balance
- production of H+ = loss of H+
Name examples of extracellular fluid in the body
- Interstitial fluid
- Blood
- Lymph
What mechanism maintains the electrolyte dominance of potassium ions in ICF and sodium ions in ECF?
- Na+/K+ pump
What type of transport does the Na+/K+ pump use?
- (Primary) Active Transport
Other than consuming moist foods and drinking beverages, how else is water “introduced” into the body?
- Metabolic generation (Cellular Respiration) because glucose + O2 -> CO2 + H2O + ATP
What regulated H2O intake?
- controlled via Thirst center in hypothalamus
What regulates H2O output? Provide an example
- controlled via DCT and CD of kidney
-> ADH released -> ⬆H2O reabsorption -> ⬇Urine output
Concentration of individual electrolytes affects a variety of _____ _______
cell functions.
Know and be able to name important electrolytes in the body
- H+
- Na+
- K+
- Ca2+
- HCO3- (bicarbonate)
- Mg
- Cl- (chloride)
- SO4 2- (sulfate)
- PO4 3- (phosphate)
Name 2 conditions that are a result of electrolyte imbalance. Name the condition and define it.
- Hyponatremia - low concentration of Na+ in the blood
- Hypernatremia - high concentration of Na+ in blood
In Acid-Base balances, what would release H+? What combines with H+?
- Acids: release H+ (proton donor)
- Bases: combine with H+ (proton acceptor)
pH affects all body systems, but which two body systems are really sensitive to pH changes?
- Nervous System
- Cardiovascular System
What pH value do you need to be below/above for it to be considered acidosis/alkalosis?
- Acidosis: below 7.35
- Alkalosis: above 7.45
Write the reaction of the bicarbonate buffer system in blood.
CO2 + H2O ⇋ H2CO3 ⇋ H+ + HCO3
Based on the normal chemical reactions that occur in the body to regulate pH, what will happen to pH if a person is holding their breath?
⬆CO2 = ⬆H+ = ⬇pH (acidic)
Based on normal chemical reactions that occur in the body to regulate pH, what will happen to pH if a person is hyperventilating?
⬇CO2 = ⬇H+ = ⬆pH (alkaline)
Name 3 important buffer systems in the body
- Protein Buffer System
- Carbonic Acid-Bicarbonate Buffer System
- Phosphate Buffer System
T/F: Buffer systems will temporarily solve the problem of acid-base imbalances
True
What is the purpose of protein buffer system in the body?
- Regulate pH of ICF and ECF by accepting/donating H+ to amino acids amine (NH2)/carboxyl group (COOH)
What is the purpose of carbonic acid-bicarbonate buffer system in the body?
Bicarb acts as weak base (accept H+) and Carbonic Acid acts as weak acid (donate H+)
What is the purpose of phosphate buffer system in the body
Regulates pH of ECF and ICF (more important to ICF) via H2PO4- (anion, weak acid) to combine/donate H+
What buffer system is MOST important to maintaining balance in ICF?
- Phosphate Buffer System
What part of the brain acts as the respiratory system?
Brainstem (medulla oblongata) regulates H+ ions by adjusting rate and depth of breathing
Describe Respiratory compensation and how this happens
- Change in respiratory system.
-> CO2 sensed by chemoreceptors in carotid/aortic bodies to signal CNS
Describe renal compensation
changes in rates of H+ and Bicarbonate ion secretion/absorption in kidney
Describe Respiratory Acidosis
Include: What is it caused by and how it leads to acidosis
- Caused by the inability to eliminate CO2, usually because of hypoventilation or abnormally low respiration rate
- Leads to acidosis because: If ⬆CO2 = ⬆H+ = ⬇pH (acidic)
Describe Respiratory Alkalosis
Include: What is it caused by and how it leads to alkalosis
- Caused by increased respiratory activity that causes drop in CO2, usually because of hyperventilation
- Leads to alkalosis because: If ⬇CO2 = ⬇H+ = ⬆pH (alkaline)
Describe Metabolic Acidosis
Include: What is it caused by and have an understanding of how it leads to acidosis
- Caused by large production of metabolic acids
- Ex: Lactic acid (anaerobic CR)
ketone bodies (fat breakdown)
kidneys not eliminated H+ (⬆H+ in body = ⬇pH)
loss of bases (nothing to combine with H+ -> ⬆H+ = ⬇pH)
Describe: Metabolic alkalosis
Include: What it is caused by and be able to describe how this will leads to alkalosis
- Caused when bicarbonate ions becomes elevated, which reduces H+ ions
- ⬆Bicarbonate = combines with lots of H+ = ⬇H+ = ⬆pH (alkaline)
If the blood becomes too acidic (low pH), the respiratory system ___ the breathing rate to ___ more CO₂, which ___ acidity.
increases
expel
reduces
If the blood becomes too alkaline (high pH), the respiratory system ____ the breathing rate to ___ CO₂, which ___ acidity.
decreases
retain
increases