Water and Organic Molecules Study Guide

Flashcards covering key vocabulary terms related to water's properties, its role in biological systems, molecular interactions, and basic chemistry calculations, derived from the provided lecture notes.

Partial negative charge on a water molecule

Located on the oxygen atom.

Partial positive charge on a water molecule

Located on the hydrogen atom.

Intracellular fluid

Fluid found inside cells, holding water and ions.

Extracellular fluid

Fluid found outside cells.

Polar molecule (water)

Has a partial positive charge on hydrogen atoms and a partial negative charge on the oxygen atom due to unequal sharing of electrons.

Hydrogen bonds

Interactions between water molecules that lead to cohesion.

Water's role as a solvent

Can dissolve polar molecules and break ionic bonds.

Molecules that dissolve in water

Ionic and polar molecules, because they are attracted by water's polarity.

Molecules that cannot dissolve in water

Non-polar molecules, because they are hydrophobic.

Importance of water as a solvent for living organisms

Allows transport of nutrients, waste, and other substances.

Polar molecule

Characterized by unequal sharing of electrons, resulting in partial charges.

Non-polar molecule

Characterized by equal sharing of electrons, resulting in no charges.

Amphipathic molecule

A molecule with both a polar part (head) and a non-polar part (tail).

Water's role in membrane formation

Causes micelles to form when amphipathic molecules are placed in water, with polar heads facing water and non-polar tails away from it.

Condensation (dehydration) reaction

Two molecules combine to form a larger molecule, releasing water.

Hydrolysis

A large molecule is broken down into smaller units by adding water.

Turgor pressure

The pressure of water inside the central vacuole of plant cells that maintains cell structure.

Water stability as a liquid

Maintained by strong hydrogen bonds.

Specific heat

The heat required to raise the temperature of 1 gram of a substance by 1 degree Celsius.

Heat capacity

The amount of heat required to raise the temperature of an entire object.

Heat of vaporization

The amount of heat required to vaporize 1 mole of a substance.

Role of Heat of vaporization in sweating

Most responsible for the dissipation of body heat when sweating.

Cohesion

The attraction between like molecules.

Adhesion

The attraction between different types of molecules.

Acidic pH values

Values less than 7.

Basic (alkaline) pH values

Values greater than 7.

Neutral pH value

A value of 7.