Water, Electrolyte and pH BALANCE Upload 17.10 Water, Electrolyte, and pH Balance Notes to eBackpack

Study the picture. 1. What do you think would be a good definition for the word “balance” in regard to water, electrolyte and pH balance? Balance: The amount entering equals the amount leaving.

Balance Two important balance concepts: *To maintain homeostasis, the quantities of water and electrolytes must be in balance. *Because electrolytes are dissolved in the water of the body fluids, water balance and electrolyte balance are interdependent.

Water balance Use your text, Chapter 18. 2. How is water intake regulated? Thirst- Osmoreceptor detect water levels How is water output regulated? Urine production

Examples of water balance Study the diagram on the next page. Carefully complete this diagram as it is likely to be on the test.

Water content of the blood HIGH Water content of the blood LOW Too much water drunk Too much salt or sweating Brain produces More ADH Brain produces Less ADH Water content of the blood normal Low volume of water reabsorbed by kidney High volume of water reabsorbed by kidney Urine output HIGH Urine output LOW (small volume of Concentrated urine) (large volume of dilute urine)

What does ADH stand for? Antidiuretic hormone How does ADH work? ADH increases the permeability of the distal convoluted tubule and collecting duct which increases water reabsorption and reduces urine production.

Water imbalance Hypothesize the correct description for each condition and then check your answers. Dehydration An abnormal accumulation of extracellular fluid in interstitial Water intoxication spaces Edema Results in a large volume of urine and concentrated blood which Use of diuretics puts pressure on brain cells Too much water results in swollen tissue causing cells to burst, may result in seizures, coma and death Water output exceed water intake resulting in dry skin , loss of body weight, and difficulty regulating temperature

Electrolyte balance Below is a picture of electrolyte balance. Fill in the arrows with Electrolyte sources for the body. Ways in which electrolytes are lost. Food Perspiration Beverages Feces By-product of Metabolic reactions Urine production

Electrolyte balance What is aldosterone? A hormone How does aldosterone help regulate electrolyte balance? Aldosterone increases sodium reabsorption, and cause tubular secretion of potassium ions.

Electrolyte imbalance Hypothesize the correct description for each condition and then check your answers. Hyponatemia When the adrenal cortex does not regulate potassium levels correctly, Hypernatremia muscle weakness may occur Hypokalemia Prolonged sweating or vomiting may result in low Na and water intoxication Hyperkalemia High potassium levels may cause paralysis During high fever high sodium levels may effect the nervous system resulting in confusion

Electrolyte imbalance A 17 year old football player in California died and the coroner’s report stated that he died of electrolyte imbalance from drinking too much water during practice. What happened? Watch this video LINK He diluted the concentration of electrolytes already low from sweating. Water entered his cells (osmosis) and they burst

pH Balance The metabolic processes of the body produce hydrogen ions. What acid is produced in each situation? Acidic Ketone Bodies Sulfuric acids Phosphoric acid Carbonic Acid Lactid Acid

pH Balance 11. Hydrogen ions are regulated by: a. An acid-base buffer system b. The respiratory center in the brain stem which increases or decreases the rate of breathing c. Nephrons in the kidneys which excrete excess H+ ions So what body systems regulate pH? Respiratory, Nervous, Urinary, Cardiovascular

pH Balance By far the most important buffer for maintaining acid-base balance in the blood is the carbonic-acid-bicarbonate buffer. The simultaneous equilibrium reactions of interest are H+ + HCO3 H2CO3 H2O + CO2 Hydrogen Ions Bicarbonate Carbonic acid water Carbon dioxide Controlled by Respiration Kidney controlled

pH Balance This figure shows the major organs that help control the blood concentrations of CO2 and HCO3- (bicarbonate), and thus help control the pH of the blood. Removing CO2 from the blood helps increase the pH. Is CO2 an acid or base? Removing HCO3- from the blood helps lower the pH. Is HCO3- an acid or base? 13. Why does high heart rate hinder CO2 removal? Blood is pumped more quickly so less time for gas exchange. Watch this video to learn about pH imbalance LINK

Try to match the component of the body with the effect of pH imbalance Enzymes Organs Microbes Oxygen Minerals Can change shape, mutate, and become pathogenic Can change from constructive to destructive Delivery to cells is decreased Can become compromised (brain, heart) Assimilation can be thrown off