Properties of Water

Flashcards about Properties of Water

Water

The most abundant biomolecule in the body, making up 60-95% of living cells.

Intracellular fluid

Fluid found inside cells, accounting for 55% of the water in the human body.

Transport medium

A function of water where it acts as a medium that carries substances in and out of cells.

Temperature regulation

A function of water that helps regulate and stabilize body temperature.

Solvent in digestion and waste excretion

A function of water where it acts as a dissolving agent to assist in digestion and waste removal.

Dehydration

The state where water loss exceeds intake.

Edema

The state where water intake exceeds loss.

Polar bond

A type of bond where electrons are unequally shared between atoms due to differences in electronegativity.

Polar molecules

Molecules with polar bonds

Hydrogen bond (H-bond)

A weak non-covalent interaction between a hydrogen atom covalently bonded to an electronegative atom and a lone pair of electrons on another electronegative atom.

H donor

The atom covalently bonded to its O atom acts in the molecule.

H acceptor

The lone pair O atom to another water molecule.

Hydrogen acceptor

Organic biomolecules containing carbonyl and carboxyl groups (aldehydes, ketones and amides) are this.

Hydrogen Acceptors and Donors

Alcohols, carboxylic acids, and amines are capable of being both of these.

Hydrophilic

Substances that can be dissolved in water.

Dipole-dipole interaction

The interaction between water and another polar molecule.

Hydrophobic

Substances that cannot be dissolved in water.

Hydrophobic effect

The effect that drives the folding of proteins and the self-assembly of biological membranes.

Amphipathic

Molecules that have both hydrophilic and hydrophobic regions.

Micelles

Structures formed by amphipathic substances in water, where non-polar tails cluster together to minimize contact with water.

Acids

Substances that donate protons.

Bases

Substances that accept protons.

pH

A measure of the hydrogen ion concentration in a solution.

Acid dissociation constant (Ka)

A constant, Ka, that expresses acid strength; the higher the value, the stronger the acid.

pKa

A quantity similar to pH, defined as pKa = -log[Ka]; the lower the value, the stronger the acid.

Buffer

A solution that resists changes in pH, composed of a weak acid and its conjugate base.

Acidosis

A condition where the blood pH is below the normal range (7.35-7.45), indicating high acidity.

Alkalosis

A condition where the blood pH is above the normal range (7.35-7.45), indicating high alkalinity.

Bicarbonate Buffer System

CO2 +H2O↔H2CO3 ↔H+ +HCO3 -

Metabolic

Acidosis or alkalosis caused by disturbance of the interaction between H+ and HCO3-.