chapter 25 a&p
Define acidemia and alkalemia.
Acidemia is the condition in which blood pH decreases below 7.35. Alkalemia is the condition in which blood pH increases above 7.45.
How would a decrease in the pH of body fluids affect the respiratory rate?
A decrease in the pH of body fluids would cause an increase in the respiratory rate.
Describe a fluid shift.
A fluid shift is a rapid movement of water between the ECF and ICF in response to an osmotic gradient.
What effect does aldosterone have on sodium ion concentration in the ECF?
Aldosterone causes increased urinary sodium retention and thus increases the sodium ion concentration in the ECF.
Summarize the relationship between Pco2 levels and pH
An inverse relationship exists between PCO2 and pH
Explain dehydration and its effect on the osmotic concentration of blood.
Dehydration is a reduction in the water content of the body that develops when water losses outpace water gains. In dehydration, the osmotic concentration of blood plasma increases.
Describe the fluid compartments
Fluid compartments are the ECF and ICF, which behave as separate sections and maintain different ionic compositions.
Define hypokalemia and hyperkalemia
Hypokalemia is a condition characterized by blood K+ levels below 3.5 mEq/L. Hyperkalemia is a condition characterized by blood K+ levels above 5.0 mEq/L
Describe metabolic acidosis
Metabolic acidosis results from the production of large numbers of fixed and metabolic acids, from the depletion of the bicarbonate reserve caused by an inability to excrete hydrogen ions at the kidneys, or from bicarbonate loss.
Describe metabolic alkalosis.
Metabolic alakalosis results from the removal of large numbers of hydrogen ions from body fluids when bicarbonate ion concentrations become elevated.
Define mineral balance.
Mineral balance is the state that exists when the body's ion gains and losses are equal.
What effects does inhibition of osmoreceptors have on ADH secretion and thirst?
Osmoreceptor inhibition leads to decreased ADH secretion and suppressed thirst
Identify factors that cause potassium excretion.
Potassium excretion increases as potassium concentrations increase in the ECF, under aldosterone stimulation, and when the pH of the ECF increases.
Which solid component make up most of the body mass?
Proteins make up most of the body mass
Explain the significance of two important body minerals: sodium and calcium
Sodium is a major cation that is essential for normal membrane function. Calcium is a cation that is essential for normal muscle and neuron function and for normal bone structure.
Define ECF and ICF
The ECF, or extracellular fluid is made up of the interstitial fluid of peripheral tissues and the plasma of circulating blood. The ICF, or interstitial fluid, consists of the cytosol inside the cells
What would happen to the blood Pco2 of a patient who has an airway obstruction?
The blood Pco2 of a patient with an airway obstruction would increase, resulting in respiratory acidosis.
Identify the body's three major buffer systems.
The body's three major buffer systems are the phosphate buffer system, the protein buffer systems, and the carbonic acid-bicarbonate buffer system.
Describe the carbonic acid-bicarbonate buffer system
The carbonic acid-bicarbonate buffer system prevents pH changes caused by metabolic acids and by fixed acids generated by metabolic activity. It uses the H+ released by these acids to generate carbonic acid, which dissociates into H2O and CO2, the latter of which is exhaled from the lungs.
What intermediate compound formed from water and carbon dioxide directly affects the pH of the ECF
The intermediate compound formed from water and carbon dioxide that directly affects the pH of the ECF is carbonic acid (H2CO3).
Identify the electrolytes absorbed by active transport
The ions absorbed by active transport are sodium, calcium, magnesium, iron, phosphate, and sulfate.
Which organs are primarily responsible for regulation the potassium ion concentration in the ECF
The kidneys are primarily responsible for regulating the potassium ion concentration in the ECF
If the kidneys are conserving HCO3-and eliminating H+ in acidic urine, which is occurring: metabolic alkalosis or metabolic acidosis?
The kidneys conserve HCO3-and eliminate H+ in the urine during metabolic acidosis.
Identify routes of fluid loss from the body.
The major routes of fluid loss are urination, evaporation at the skin and at the lungs, and water lost in feces.
Which fluids are buffered by the phosphate buffer system?
The phosphate buffer system plays an important role in buffering the pH of the ICF and the urine.
What is the primary challenge to acid-base homeostasis?
The primary challenge to acid-base homeostasis is that your body generates a variety of acids during normal metabolic operations, and a significant decrease in body fluid pH must be prevented.
Compare the three categories of acids.
Volatile acids can leave solution an enter the atmosphere. Fixed acids remain in body fluids until excreted by the kidneys. Metabolic acids are participants in, or by-products of, cellular metabolism.
When is your body in acid-base balance?
when the production of hydrogen ions is precisely offset by their loss and when the pH of body fluids remains within normal limits.
