BIO 108: Fluid, Electrolyte & Acid-Base Balance

Fluid Compartments

Intracellular fluid (ICF) - cytosol - the fluid __ cells, __ of body fluid.

within, 2/3

Fluid Compartments

Extracellular fluid (ECF) - the fluid __ of cells, __ of body fluid.

outside, 1/3

Fluid Barriers

What separates intercellular fluid from surrounding interstitial fluid?

Plasma membrance

Fluid Barriers

What divides interstitial fluid from blood plasma?

Blood vessels

Body Water Gain & Loss

What are three ways the body gain water?

Ingested fluids, ingested foods, and metabolic water.

Body Water Gain & Loss

What are four ways the body lose water?

Kidneys (urine), skin (sweat), lungs (vapor), and GI tract (feces).

Regulation

What regulates the body’s gain of water?

Thirst center of hypothalamus

Regulation

What regulates the body’s loss of water?

ADH → reabsorbs water, Angiotensin II and Aldosterone → reabsorbs Na and Cl, ANP → excretes Na and Cl

Movement Between ICF & ECF

An increase in osmolarity of interstitial fluid will cause cells to __.

Shrink (draws fluid out the cell).

Movement Between ICF & ECF

A decrease in osmolarity of interstitial fluid will cause cells to __.

Swell (draws fluid into the cell).

Movement Between ICF & ECF

Changes in osmolarity is the cause of __.

fluid imbalance.

Movement Between ICF & ECF

What is the most common reason for change in osmolarity?

Na

All are general functions of electrolyte balance EXCEPT:

All choices are functions of electrolyte balance.

Cation are __.

positive.

Anion are __.

negative.

Electrolyte Elements

Sodium - is a __, is most abundant in __, and is needed for __.

cation, ECF, action potentials in muscle and nerve tissue.

Electrolyte Elements

Chloride - is a __ and is most abundant in __.

anion, ECF.

Electrolyte Elements

Potassium - is a __ and is most abundant in __.

cation, ICF.

Electrolyte Elements

Bicarbonate - is a __, is most abundant in __, and concentration decreases when __.

anion, ECF, when CO2 is exhaled.

Electrolyte Elements

Calcium - is a __ and is most abundant in __.

cation, the body due to bones.

Electrolyte Elements

Phosphate - is a __ and acts as __.

anion, an important buffer inside cells.

Electrolyte Elements

Magnesium - is a __, it is found in __, and is needed for __.

cation, in bone, neuromuscular activity & cofactor for enzymes.

Acid-Base Balance

What are the 3 types of buffer systems in acid-base balance?

Protein, carbonic acid, and phosphate.

Acid-Base Balance

Which buffer system is vey abundant, and works in both ICF & ECF compartments?

Protein buffer system

Acid-Base Balance

Which buffer system act on the ECF only, and binds to free H in low pH?

Carbonic acid buffer system

Acid-Base Balance

Which buffer system acts predominately inside of cell (ICF)?

Phosphate buffer system

Acid-Base Balance

Body’s pH below 7.35 is __.

acidosis.

Acid-Base Balance

Body’s pH above 7.45 is __.

alkalosis.

Acid-Base Balance

Respiratory compensation - the use of __ to correct pH imbalance.

the respiratory system

Acid-Base Balance

Renal compensation - using __ to secrete H+, or reabsorb __ to correct pH imbalance.

kidneys, HCO3

Acid-Base Balance

Respiratory Acidosis - is an increase in __ and a decrease in __.

CO2, pH.

Acid-Base Balance

Respiratory Alkalosis - is an increase in __ and a decrease in __.

pH, CO2.

Acid-Base Balance

Metabolic Acidosis - is a __ in pH and a __ in HCO3.

decrease, decrease

Acid-Base Balance

Metabolic Alkalosis - is an __ in pH and an __ in HCO3.

increase, increase

Relationship between PCO2 and Plasma pH

If PCO2 rises, then __.

pH falls, and acidosis develops.

Relationship between PCO2 and Plasma pH

If PCO2 falls, then __.

pH rises, and alkalosis develops.

Exhalation of Carbon Dioxide

Decrease in pH → breathing __.

faster (blow off more CO2).

Exhalation of Carbon Dioxide

Increase in pH → breathing __.

slows (blow off less CO2).