Biochemistry and Properties of Water Review

Comprehensive vocabulary flashcards covering subatomic particles, ions, polarity, properties of water, solutions, pH, and the four major biological macromolecules based on the Unit 2 review sheet.

Proton

A subatomic particle located in the nucleus with a positive charge.

Neutron

A subatomic particle located in the nucleus with a neutral charge.

Electron

A subatomic particle orbiting the nucleus with a negative charge.

Ion

An atom or molecule that carries an electrical charge due to an unequal number of protons and electrons.

Cation

A positively charged ion that forms when an atom has more protons than electrons.

Anion

A negatively charged ion that forms when an atom has more electrons than protons.

Molecule

A chemical structure composed of two or more atoms bonded together, such as $O_2$ or $H_2O$.

Compound

A substance composed of two or more different elements chemically bonded together, such as $NaCl$ or $H_2O$.

Polar Molecule

A molecule that has an uneven distribution of charge, resulting in slightly positive regions (at the hydrogen atoms in water) and a slightly negative region (at the oxygen atom).

Hydrogen Bond

A weak intermolecular attraction formed between the slightly positive hydrogen end of one water molecule and the slightly negative oxygen end of another.

Cohesion

The property of water molecules being attracted to and sticking to other water molecules.

Adhesion

The property of water molecules being attracted to and sticking to different substances or surfaces.

High Specific Heat

The ability of water to resist changes in temperature, which prevents sudden temperature fluctuations and helps organisms regulate internal body heat.

Less Dense as a Solid

The property of water whereby solid ice floats on liquid water because its molecules are arranged in a less dense structure, insulating aquatic life below.

Universal Solvent

A title given to water because it dissolves more substances than any other liquid, enabling it to carry essential nutrients in blood and cells.

Surface Tension

A cohesive force at the surface of a body of water that resists external force, allowing small organisms like water striders to walk on water without sinking.

Capillary Action

The upward movement of water through narrow spaces (such as inside paper towels or from tree roots to leaves), produced by the combination of cohesion and adhesion.

Solute

The substance that is dissolved into a liquid, such as salt or sugar.

Solvent

The dissolving agent of a solution, such as water, that dissolves other substances.

Solution

A homogeneous mixture formed when one or more solutes are evenly dissolved throughout a solvent, such as salt water.

Hydrophilic

"Water-loving"; describes substances like table salt and sugar that interact with and dissolve easily in water.

Hydrophobic

"Water-fearing"; describes nonpolar substances like cooking oils, butter, and fats that do not dissolve in water.

pH Scale

A measurement scale where pure water has a neutral value of $7$, values below $7$ are acidic (such as $2$ or $6.5$), and values above $7$ are basic (such as $9$ or $13$).

Organic Compound

A chemical compound that contains carbon-hydrogen bonds, such as glucose ($C_6H_{12}O_6$) and methane ($CH_4$).

Inorganic Compound

A chemical compound that lacks carbon-hydrogen bonds, such as water ($H_2O$), table salt ($NaCl$), and hydrochloric acid ($HCl$).

SPONCH

An acronym representing the six essential chemical elements that make up living matter: Sulfur ($S$), Phosphorus ($P$), Oxygen ($O$), Nitrogen ($N$), Carbon ($C$), and Hydrogen ($H$).

Monomer

A single molecular building block that joins with other repeating units to construct a larger molecule.

Polymer

A large molecule formed by bonding many repeating monomers together.

Carbohydrate

A biological macromolecule composed of Carbon, Hydrogen, and Oxygen ($CHO$) that serves as a quick energy source or energy storage.

Monosaccharide

The single-sugar monomer unit of carbohydrates (such as glucose) used by cells for quick energy.

Polysaccharide

A large carbohydrate polymer composed of many linked monosaccharides, used for energy storage.

Starch

A storage polysaccharide found in plants (such as potatoes) that holds excess glucose for energy.

Glycogen

A storage polysaccharide found in animals that stores excess glucose in tissues.

Lipid

A hydrophobic macromolecule composed of Carbon, Hydrogen, and Oxygen ($CHO$) used for long-term energy storage, insulation, and membrane structure.

Triglyceride

A fat molecule assembled from $1$ glycerol molecule bonded to $3$ fatty acid chains.

Phospholipid

A specialized lipid that forms the cell membrane, regulating which substances enter and exit the cell.

Protein

A macromolecule composed of Carbon, Hydrogen, Oxygen, Nitrogen ($CHON$), and sometimes Sulfur ($S$) that functions in structure, defense, catalysis, and signaling.

Amino Acid

The monomer building block of proteins that links together to form peptide polymers.

Enzyme

A protein that carries out chemical reactions in the cell by building molecules up or breaking them down.

Antibody

A specialized protein that defends the body by fighting infections and breaking down foreign substances.

Nucleic Acid

A macromolecule composed of Carbon, Hydrogen, Oxygen, Nitrogen, and Phosphorus ($CHONP$) that stores, transmits, and expresses genetic information.

Nucleotide

The monomer of nucleic acids, built from three distinct parts and assembled to form DNA and RNA.