[26.5 - 26.6] Fluid, electrolyte, acid base balance (2026)

A series of vocabulary flashcards based on fluid, electrolyte, and acid-base balance in human anatomy and physiology.

Body Fluid Compartments

Refers to the distinct areas within the body where fluids are located, specifically intracellular and extracellular compartments.

Intracellular Fluid (ICF)

The fluid inside cells, accounting for about 2/3 of total body fluid.

Extracellular Fluid (ECF)

Fluid outside of cells, including plasma and interstitial fluid, accounting for 1/3 of total body fluid.

Solutes

Substances dissolved in water; classified into nonelectrolytes and electrolytes.

Nonelectrolytes

Organic molecules that do not dissociate in water. Examples include glucose, lipids, and creatinine.

Electrolytes

Substances that dissociate into ions in water, conducting electricity and causing fluid shifts.

Osmolality

A measure of the concentration of solutes in a solution, maintained at around 280–300 mOsm in body fluids.

Thirst Mechanism

Regulated by the hypothalamus, it drives water intake based on changes in osmolality and blood volume.

Antidiuretic Hormone (ADH)

Hormone that regulates water reabsorption in the kidneys; increased ADH leads to concentrated urine.

Dehydration

A water balance disorder characterized by a significant loss of water in the body, leading to symptoms such as thirst and dry skin.

Edema

The atypical accumulation of interstitial fluid, resulting in tissue swelling.

Aldosterone

Hormone that plays a primary role in regulating sodium balance and water retention in the body.

Sodium (Na⁺)

The most abundant cation in extracellular fluid, crucial for fluid balance and osmotic pressure.

Potassium (K⁺)

A major cation in intracellular fluid, important for resting membrane potential in cells.

Parathyroid Hormone (PTH)

Hormone responsible for regulating calcium balance by increasing blood calcium levels.

Chloride (Cl⁻)

The major anion accompanying Na⁺ in extracellular fluid, important for maintaining osmotic pressure.

Homeostasis

The process by which the body maintains a stable internal environment.