2C 2D

Electrolyte

Substance that separates into ions in water and can conduct electrical current.

Ion

An atom with an unequal number of electrons and protons.

Osmosis

Passive diffusion of water across a semipermeable membrane.

Hypertonic solution

A concentrated solution where water is drawn out of cells, causing shrinkage.

Isotonic solution

A solution with equal solute concentration on both sides of the cell membrane.

Hypotonic solution

A low solute concentration solution where water moves into cells, causing swelling.

Mineral

Naturally occurring inorganic, solid substance not synthesized in the body.

Bioavailability

The amount of a nutrient that is absorbed and available to the body.

Intracellular fluid (ICF)

Fluid inside body cells, representing two-thirds of all body water.

Extracellular fluid (ECF)

Fluid outside cells, split into interstitial fluid and intravascular fluid.

How osmosis maintains fluid balance

The body pumps electrolytes, forcing water to follow via osmosis to balance fluid shifts.

Major physiological roles of water

Blood volume, secretions, solvent, tissue moisture, chemical reactions, temperature regulation, and waste removal.

Water AI (Adequate Intake) for adults

15 cups for men; 11 cups for women.

Antidiuretic hormone (ADH) trigger and effect

Triggered by high osmotic pressure; signals kidneys to conserve water.

Aldosterone trigger and effect

Triggered by low blood pressure; signals kidneys to retain sodium.

Effects of water underconsumption

Dehydration, low blood pressure, increased heart rate, kidney failure, coma, or death.

Effects of water overconsumption

Water intoxication, diluted ECF sodium, water shifting into brain cells, brain swelling.

Bioavailability inhibitors

Phytic acid, oxalic acid, polyphenols, and low gastric acidity.

Bioavailability enhancer

Vitamins, such as Vitamin C boosting iron absorption.

Sodium AI and CDRR/UL

AI is 1500 mg/day; Chronic Disease Risk Reduction standard is 2300 mg/day.

Sodium primary function

Primary positive ion regulating extracellular fluid volume and water balance.

Hyponatremia

Sodium deficiency causing muscle cramps, headaches, nausea, confusion, and fatigue.

Sodium toxicity effect

Contributes directly to hypertension (high blood pressure) and cardiovascular risk.

Potassium AI

3400 mg/day for men; 2600 mg/day for women.

Potassium primary function

Premier positive ion of intracellular fluid, dictating cellular water balance.

Hypokalemia

Potassium deficiency causing irregular heartbeats, muscle weakness, severe cramps, and appetite loss.

Hyperkalemia

Potassium toxicity causing dangerous slowing of heartbeat or cardiac arrest.

Chloride primary functions

Main negative extracellular ion for water balance; used to make stomach hydrochloric acid.

Chloride deficiency cause and symptoms

Caused by severe vomiting; symptoms include weakness, lethargy, and acid-base disruptions.

Calcium RDA (19-50 years)

1000 mg/day for adults.

Calcium storage

99% is stored structurally within bones and teeth.

Calcium deficiency effects

Osteopenia, osteoporosis, and tetany (uncontrolled muscle spasms).

Calcium toxicity effects

Kidney stones, hypercalcemia, and impaired absorption of other divalent minerals.

Phosphorus RDA

700 mg/day.

Phosphorus primary functions

Bone structure, ATP component, phospholipids, DNA/RNA backbones, and intracellular buffer.

Hyperphosphatemia

Phosphorus toxicity causing non-skeletal tissue calcification and accelerated bone loss.

Magnesium RDA

400-420 mg/day for men; 310-320 mg/day for women.

Magnesium functions

Bone structure and cofactor for over 300 enzyme systems utilizing ATP.

Magnesium deficiency effects

Muscle weakness, spasms, and severe seizures (common in alcoholics).

Sulfur physiological functions

Forms disulfide bridges to stabilize proteins (collagen, hair, nails); drug detoxification.

Major vs. Trace minerals

Major minerals are needed in >=100 mg/day; trace minerals in <100 mg/day.

Iron RDA

8 mg/day for men; 18 mg/day for women.

Heme vs. Nonheme iron sources

Heme: animal flesh. Nonheme: vegetables, grains, enriched flour, supplements.

Iron transport and storage proteins

Transported by transferrin; stored inside cells bound to ferritin.

Iron deficiency effect

Microcytic, hypochromic anemia (small, pale red blood cells).

Hemochromatosis

Genetic chronic iron overload causing accumulation that damages liver, heart, and pancreas.

Zinc RDA

11 mg/day for men; 8 mg/day for women.

Metallothionein

Binding protein that traps zinc and copper in enterocytes to block excess absorption.

Zinc deficiency effects

Growth retardation, dermatitis, diarrhea, immune dysfunction, hair loss, loss of taste.

Zinc toxicity and copper interaction

Chronic excess zinc induces metallothionein, which traps and prevents copper absorption.

Copper RDA

900 micrograms/day.

Copper physiological functions

Oxidizes iron via ceruloplasmin/hephaestin, acts as antioxidant, and aids ATP production.

Menkes disease

Genetic progressive neurological disorder preventing copper absorption from intestinal cells.

Wilson disease

Genetic toxicity where copper accumulates in liver and brain due to defective excretion.

Manganese AI

2.3 mg/day for men; 1.8 mg/day for women.

Manganese toxicity effect

Severe neurological damage with symptoms mimicking Parkinson's disease.

Iodine RDA

150 micrograms/day.

Iodine physiological function

Essential component of thyroid hormones T4 and T3 to regulate metabolism.

Cretinism

Maternal iodine deficiency causing mental retardation and short stature in offspring.

Selenium RDA

55 micrograms/day.

Selenium physiological function

Antioxidant defense in glutathione peroxidase; converts T4 to active T3.

Keshan disease

Specific cardiomyopathy (heart muscle disease) associated with selenium deficiency.

Selenosis

Selenium toxicity causing hair/nail loss, nausea, fatigue, and garlic-like breath.

Chromium AI

35 micrograms/day for men; 25 micrograms/day for women.

Chromium physiological function

Enhances insulin action to promote cellular glucose uptake and normalize blood glucose.

Fluoride AI

4 mg/day for men; 3 mg/day for women.

Fluoride physiological function

Converts hydroxyapatite to fluorapatite, making dental enamel harder and decay-resistant.

Fluorosis

Toxicity caused by chronic excess fluoride in children during tooth development.

Trace vs. Ultratrace minerals

Trace minerals: <100 mg/day. Ultratrace minerals: <1 mg/day.

Molybdenum (Mo) function

Cofactor for enzymes metabolizing sulfur-containing amino acids and purines.

Boron (B) proposed role

Plays a role in bone health, steroid hormone metabolism, and brain function.

Nickel (Ni) proposed role

Cofactor for amino acid/lipid metabolism; structural role in membranes.

Silicon (Si) proposed role

Involved in bone mineralization, collagen synthesis, and connective tissue integrity.

Vanadium (V) proposed role

Mimics or enhances insulin action in pharmacological doses.

Arsenic (As) proposed role

Participates in amino acid metabolism and gene expression in tiny amounts.