Fluid, Electrolyte and Acid-Base Balance

These flashcards cover vocabulary related to fluid, electrolyte, and acid-base balance in the human body.

Intracellular Fluid (ICF)

Fluid inside cells that accounts for 2/3 of total body fluid.

Extracellular Fluid (ECF)

Fluid outside of cells that accounts for one-third of total body fluid, including plasma and interstitial fluid.

Plasma

The liquid component of blood, accounting for 3 liters of ECF.

Interstitial Fluid (IF)

Fluid in spaces between cells, accounting for 12 liters of ECF.

Solutes

Substances dissolved in water; classified as nonelectrolytes and electrolytes.

Nonelectrolytes

Organic molecules that do not dissociate in water; examples include glucose and urea.

Electrolytes

Substances that dissociate into ions in water, such as salts, acids, and bases.

Ion

An atom or molecule that carries a charge, capable of conducting electricity.

Major cation in ECF

Sodium (Na+).

Major anion in ECF

Chloride (Cl-).

Major cation in ICF

Potassium (K+).

Major anion in ICF

Hydrogen phosphate (HPO4 2-).

Thirst mechanism

The driving force for water intake, governed by hypothalamic osmoreceptors.

Obligatory water losses

Essential water loss that cannot be eliminated, including losses through urine and respiration.

ADH (Antidiuretic Hormone)

Hormone that concentrates urine by promoting water reabsorption in the kidneys.

Dehydration

ECF water loss leading to symptoms like thirst and dry skin.

Hypotonic hydration

Cellular overhydration or water intoxication, leading to swollen cells.

Edema

Atypical accumulation of interstitial fluid resulting in tissue swelling.

Aldosterone

Hormone that regulates sodium balance and water retention in the kidneys.

Atrial Natriuretic Peptide (ANP)

Hormone that decreases blood pressure and volume by promoting Na+ and water excretion.

Hyperkalemia

Increased potassium levels in ECF, causing decreased resting membrane potential.

Hypokalemia

Decreased potassium levels in ECF, resulting in hyperpolarization and non-responsiveness.

Calcium balance

Controlled by parathyroid hormone (PTH); calcium is mainly found in bones.

Body pH

A measure of acidity or alkalinity of body fluids; normal arterial pH is around 7.4.

Acidosis

Condition where arterial pH is less than 7.35.

Alkalosis

Condition where arterial pH is greater than 7.45.

Chemical buffer systems

Rapid response systems that resist pH changes in body fluids.

Bicarbonate buffer system

Buffer system that includes carbonic acid (H2CO3) and bicarbonate (HCO3-).

Respiratory regulation of H+

Elimination of CO2 to maintain acid-base balance in the body.

Renal regulation

Kidneys manage acid-base balance by adjusting bicarbonate and hydrogen ion levels.

Respiratory acidosis

Acid-base imbalance caused by respiratory failure.

Metabolic acidosis

Acid-base imbalance indicated by low bicarbonate levels.

Metabolic alkalosis

Acid-base imbalance indicated by high bicarbonate levels.

Excess sodium bicarbonate ingestion

Can lead to metabolic alkalosis by increasing alkaline reserve.