Total Body Water Content and Fluid Compartments

These flashcards cover key concepts related to total body water content, fluid compartments, and the composition of fluids in the human body.

Total Body Water (TBW)

The total amount of water in the body, influenced by weight, age, sex, body composition, and body fat.

Extracellular Fluid (ECF)

Body fluid found outside the cells, comprising plasma, interstitial fluid, and other fluids.

Intracellular Fluid (ICF)

Body fluid contained within cells, also known as cytoplasm.

Percentage of water in adult males

Approximately 60% of adult male body weight is composed of water.

Percentage of water in adult females

Approximately 50% of adult female body weight is composed of water.

Age and body water relationship

Total body water decreases with age.

Nonelectrolytes

Substances that do not dissociate in solution, such as glucose and proteins.

Electrolytes

Chemicals that dissociate into ions in water and have greater osmotic power than nonelectrolytes.

Fluid compartments in the body

The two main compartments are extracellular fluid (1/3) and intracellular fluid (2/3) of total body water.

Comparison of body water in different age groups

Infants are about 73% water, normal adults about 60%, and elderly individuals decline to about 45% water.

Effect of body composition on water content

Muscle tissue contains more water than adipose (fat) tissue.

Skeletal muscle

Voluntary muscle tissue that is about 65% water.

Osmotic power of electrolytes vs nonelectrolytes

Electrolytes have a greater osmotic power than nonelectrolytes.