BIOS 256 (A&P 4) WEEK 5 STUDY GUIDE
● Fluid distribution in extracellular and intracellular compartments
o The intracellular fluid (ICF)( 63%) compartment is the system that
includes all fluid enclosed in cells by their plasma membranes.
(WITHIN)(AKA cytosol)
o Extracellular fluid (ECF) (37%).Surrounds all cells in the body.
Extracellular fluid has two primary constituents: the fluid component
of the blood (called plasma) and the interstitial fluid (IF) that
surrounds all cells not in the blood.
▪ Includes: blood plasma, interstitial fluid, lymph, CSF, GI tract
fluid, synovial fluid, fluids of the eyes & ears, pleural,
pericardial & peritoneal fluids, and glomerular filtrate.
● How is thirst stimulated?
o When water loss is greater than water gain, dehydration (a decrease in
osmolarity of body fluids) stimulates thirst.
o Neurons in the mouth that detect dryness due to a decrease in flow of
saliva
o baroreceptors that detect lowered blood pressure in the heart and
blood vessels
o Thirst center is located in the hypothalamus
● What is pH scale, what does it measure?
o a measure of the number of H+ ions in a solution. How acidic or basic
a solution is.
● Electrolyte concentrations in extracellular and intracellular
compartments
o Extracellular- Sodium and Chlorine are most abundant
o Intracellular- Potassium & proteins and phosphates
● What happens in
o Respiratory Acidosis
▪ Increased Pco2 (above 45 mmHg) & decreased pH (below 7.35)
if no compensation.
▪ Causes: Hypoventilation due to emphysema, pulmonary edema,
trauma to respiratory center, airway obstruction or dysfunction.
, ▪ Compensatory Mechanism- Renal: increased excretion of H+.
Increased reabsorption of HCO3-. If complete pH will be w/in
normal ranges but Pco2 will be high.
o Respiratory Alkalosis
▪ Decreased Pco2 (below 35 mmHg) & increased pH (above
7.45) if no compensation
▪ Causes: Hyperventilation due to O2 deficiency, pulmonary
disease, CVA or severe anxiety.
▪ Compensatory Mechanism- Renal: decreased excretion pf H+,
decreased reabsorption of HCO3-. If complete pH will be w/in
normal range but Pco2 will be low.
o Metabolic Acidosis
▪ Decreased HCO3- (below 22) and decreased pH (below 7.35) if
no compensation
▪ Causes- loss of bicarbonate ions due to diarrhea, accumulation
of acid(ketosis), renal dysfunction
▪ Compensatory Mechanism- Respiratory: hyperventilation
which increases the loss of CO2. If complete pH will be w/in
normal range but HCO2- will be low
o Metabolic Alkalosis
▪ Increased HCO3- (above 26) & increased pH (above 7.45) if no
compensation
▪ Causes: Loss of acid due to vomiting, gastric suctioning, or use
of certain diuretics, excessive intake of alkaline drugs.
▪ Compensatory Mechanism- Respiratory: hypoventilation which
slows CO2 loss. If complete pH will be w/in normal range but
HCO3- will be high.
● Body’s responses in low blood pressure or low blood volume
o low blood volume= hypovolemia
▪ a rapid fluid loss that results in multiple organ failures,
inadequate perfusion.
o low blood pressure
▪ causes an inadequate blood flow ro the organs, can cause sroke
● Functions of electrolytes
o Inorganic compounds that dissociate into ions when dissolved in
water, conduct electricity
● Fluid distribution in extracellular and intracellular compartments
o The intracellular fluid (ICF)( 63%) compartment is the system that
includes all fluid enclosed in cells by their plasma membranes.
(WITHIN)(AKA cytosol)
o Extracellular fluid (ECF) (37%).Surrounds all cells in the body.
Extracellular fluid has two primary constituents: the fluid component
of the blood (called plasma) and the interstitial fluid (IF) that
surrounds all cells not in the blood.
▪ Includes: blood plasma, interstitial fluid, lymph, CSF, GI tract
fluid, synovial fluid, fluids of the eyes & ears, pleural,
pericardial & peritoneal fluids, and glomerular filtrate.
● How is thirst stimulated?
o When water loss is greater than water gain, dehydration (a decrease in
osmolarity of body fluids) stimulates thirst.
o Neurons in the mouth that detect dryness due to a decrease in flow of
saliva
o baroreceptors that detect lowered blood pressure in the heart and
blood vessels
o Thirst center is located in the hypothalamus
● What is pH scale, what does it measure?
o a measure of the number of H+ ions in a solution. How acidic or basic
a solution is.
● Electrolyte concentrations in extracellular and intracellular
compartments
o Extracellular- Sodium and Chlorine are most abundant
o Intracellular- Potassium & proteins and phosphates
● What happens in
o Respiratory Acidosis
▪ Increased Pco2 (above 45 mmHg) & decreased pH (below 7.35)
if no compensation.
▪ Causes: Hypoventilation due to emphysema, pulmonary edema,
trauma to respiratory center, airway obstruction or dysfunction.
, ▪ Compensatory Mechanism- Renal: increased excretion of H+.
Increased reabsorption of HCO3-. If complete pH will be w/in
normal ranges but Pco2 will be high.
o Respiratory Alkalosis
▪ Decreased Pco2 (below 35 mmHg) & increased pH (above
7.45) if no compensation
▪ Causes: Hyperventilation due to O2 deficiency, pulmonary
disease, CVA or severe anxiety.
▪ Compensatory Mechanism- Renal: decreased excretion pf H+,
decreased reabsorption of HCO3-. If complete pH will be w/in
normal range but Pco2 will be low.
o Metabolic Acidosis
▪ Decreased HCO3- (below 22) and decreased pH (below 7.35) if
no compensation
▪ Causes- loss of bicarbonate ions due to diarrhea, accumulation
of acid(ketosis), renal dysfunction
▪ Compensatory Mechanism- Respiratory: hyperventilation
which increases the loss of CO2. If complete pH will be w/in
normal range but HCO2- will be low
o Metabolic Alkalosis
▪ Increased HCO3- (above 26) & increased pH (above 7.45) if no
compensation
▪ Causes: Loss of acid due to vomiting, gastric suctioning, or use
of certain diuretics, excessive intake of alkaline drugs.
▪ Compensatory Mechanism- Respiratory: hypoventilation which
slows CO2 loss. If complete pH will be w/in normal range but
HCO3- will be high.
● Body’s responses in low blood pressure or low blood volume
o low blood volume= hypovolemia
▪ a rapid fluid loss that results in multiple organ failures,
inadequate perfusion.
o low blood pressure
▪ causes an inadequate blood flow ro the organs, can cause sroke
● Functions of electrolytes
o Inorganic compounds that dissociate into ions when dissolved in
water, conduct electricity
