The Chemical Basis of Life

A set of flashcards covering key vocabulary and concepts from Chapter Two: The Chemical Basis of Life, focusing on matter, elements, atoms, bonding, and biological molecules.

Matter

Anything that has mass and takes up space.

States of Matter

The three forms of matter: solid (definite shape and volume), liquid (definite volume, changeable shape), and gas (changeable shape and volume).

Element

A unique substance that cannot be broken down by ordinary chemical means.

Atom

The building block for each element.

Atomic Symbol

One or two letter chemical shorthand for each element.

Physical Properties

Characteristics of a substance that can be observed or measured without changing its chemical composition.

Chemical Properties

How an atom interacts with another atom, indicating its reactivity.

Trace Elements

Elements required in minute amounts, making up 0.01% of the body, often serving as parts of enzymes.

Neutron

A subatomic particle with no charge, weighing one atomic mass unit, located in the nucleus.

Proton

A positively charged subatomic particle, weighing one atomic mass unit, located in the nucleus.

Electron

A negatively charged subatomic particle with negligible mass, found in the electron cloud surrounding the nucleus.

Atomic Number

The number of protons in an atom, defining the element.

Mass Number

The total number of protons and neutrons in the nucleus of an atom.

Isotopes

Atoms of the same element that have different numbers of neutrons.

Valence Shell

The outermost shell of an atom, where bonding occurs.

Ionic Bond

A chemical bond formed when one atom loses an electron and another accepts it, creating charged ions.

Covalent Bond

A bond formed by the sharing of electrons between atoms.

Hydrogen Bond

A weak attraction between a hydrogen atom and another atom, significant for the properties of water.

Molecule

Two or more atoms held together by a chemical bond.

Compound

A substance formed from two or more different kinds of atoms chemically combined.

Solubility

The ability of one substance to dissolve in another.

Electrolytes

Ions in a solution that conduct electricity when dissolved in water.

Chemical Reaction

A process where chemical bonds are broken, formed, or rearranged, involving reactants producing products.

Activation Energy

The energy required to initiate a chemical reaction.

Enzyme

A biological catalyst that speeds up a chemical reaction by lowering activation energy.

DNA

Deoxyribonucleic acid, the genetic material of a cell, composed of nucleotides.

RNA

Ribonucleic acid, a single-stranded molecule involved in protein synthesis.

Carbohydrates

Organic compounds made of carbon, hydrogen, and oxygen, typically with a 1:2:1 ratio.

Lipids

Hydrophobic organic compounds, including fats and oils, composed predominantly of carbon and hydrogen.

Proteins

Organic molecules made from amino acids, essential for structure and function in the body.

Nucleic Acids

Biological macromolecules composed of nucleotides; includes DNA and RNA.