Fluid Balance, Electrolytes, and Micronutrient Roles in Human Physiology

Intracellular Fluid (ICF)

Fluid found inside every type of cell (e.g., blood, bone, muscle, adipose); it makes up approximately 2/3 or 63% of total body fluid.

Extracellular Fluid (ECF)

Fluid found outside the cells, making up about 1/3 or 37% of total body fluid; it includes interstitial fluid (between cells) and intravascular fluid (blood and lymph).

Osmosis (Water Movement)

The process where water moves from a LOW solute concentration to a HIGH solute concentration; water follows electrolytes.

Sodium-Potassium Pump

An active controller that uses ATP energy to move ions against their concentration gradient; it pumps 3 Sodium ($Na^+$) out of the cell and 2 Potassium ($K^+$) into the cell.

Sodium (Na) Needs

The recommended intake range is 1,500 - 2,300 mg/day.

Potassium (K) Deficiency

Symptoms include weakness, fatigue, constipation, irregular heartbeat, and increased risk of blood pressure and stroke.

Iron (Fe) Functions

1) Hemoglobin/Myoglobin for oxygen transport 2) Energy metabolism (Citric acid cycle/ETC) 3) Brain/Immune function (neurotransmitter synthesis and infection prevention).

Iron Deficiency (Anemia)

Characterized by microcytic hypochromic red blood cells (small, pale cells) and decreased hematocrit and hemoglobin levels.

Zinc (Zn) Deficiency

Causes delayed growth and sexual maturation, loss of appetite, dermatitis, hair loss, poor wound healing, and immune dysfunction.

Vitamin K Sources

Found in green leafy vegetables, broccoli, peas, beans, and plant oils.

Vitamin K Deficiency Risks

Risks include being a newborn (low stores at birth/no gut bacteria), prolonged antibiotic use, impaired fat absorption, or excess Vitamin A and E intake.