Chapter 2: Chemistry of Life Practice Flashcards

Vocabulary practice flashcards covering basic chemistry concepts, subatomic particles, chemical bonds, types of energy, reactions, and organic molecules based on the Chapter 2 lecture notes.

Matter

Substance that occupies space and has mass; composed of elements.

Mass

Amount of matter contained in the object.

Weight

Mass as effected by the pull of gravity.

Element

Substance that cannot be created or broken down by ordinary chemical means.

Atom

Smallest quantity of an element.

Protons

Positively-charged particles; found in nucleus.

Neutrons

Neutral particles that lack charge; found in nucleus.

Electrons

Negatively-charged particles; orbit nucleus.

Atomic number

The number of protons in the nucleus of an atom.

Isotope

An element that contains a different number of neutrons than protons; possibly radioactive.

Atomic mass

Sum of the number of protons and the number of neutrons in the nucleus.

Molecule

$2$ atoms held together by a chemical bond.

Chemical Compound

$2$ or more atoms of different elements held together by a chemical bond.

Valence Shell

The outermost electron shell.

Cation

A positively charged ion formed by an atom losing an electron.

Anion

A negatively charged ion formed by an atom gaining an electron.

Ionic bond

An association between ions of opposite charge.

Covalent bond

Formed when electrons are shared in a mutually-stabilizing relationship.

Non-polar molecules

When no region of a molecule is more positive or negative than the other.

Polar molecules

When a molecule contains regions that have opposite electrical charges due to an unequal sharing of electrons.

Partial charges

When the strength of a charge is less than one full electron.

Hydrogen bond

A bond formed when a weakly positive hydrogen atom already bonded to an electronegative atom is attracted to another electronegative atom from another molecule.

Anabolic reactions

Reactions that use energy.

Catabolic reactions

Reactions that require energy.

Potential energy

Energy stored in the bonds between atoms and molecules.

Exergonic reactions

Chemical reactions that release more energy than they absorb.

Endergonic reactions

Chemical reactions that absorb more energy than they release; require energy.

Kinetic energy

Energy that powers any type of matter in motion.

Mechanical energy

Energy that directly powers the movement of matter.

Radiant energy

Energy emitted and transmitted as waves rather than matter, such as light.

Electrical energy

Energy that contributes to the voltage changes that help transmit impulses in nerve and muscle cells; supplied by electrolytes in cells and body fluids.

Reactant

Substances that enter the reaction.

Product

Substances that are produced in the reaction.

Synthesis reaction

When $2$ components bond to make a larger molecule using energy.

Decomposition reaction

When bonds of a larger molecule are broken to create smaller products.

Exchange reaction

When bonds are formed and broken so that the components of the reactants are rearranged.

Enzymes

Catalyst composed of protein or ribonucleic acid; lower the level of energy that needs to be invested in a chemical reaction.

Catalyst

Any substance that increases the rate of a chemical reaction without itself undergoing any change.

Hydrolysis

When a molecule of water disrupts a compound, breaking its bonds; this reaction requires water.

Dehydration Synthesis

When one reactant gives up an atom of hydrogen and another reactant gives up a hydroxyl group to make a particular product, resulting in the formation of water.

Acids

A substance that releases hydrogen ions into water, measured by pH; the lower the pH, the more acidic.

Base

A substance that releases hydroxyl ions in water, measured by pH; the higher the pH, the more basic.

Monosaccharides

Simplest form of a carbohydrate, such as glucose, fructose, galactose, deoxyribose, and ribose.

Disaccharides

Two monosaccharides bound together, such as sucrose, lactose, and maltose.

Polysaccharides

Chains of monosaccharides, such as starches and glycogen.

Carbohydrates

Substance responsible for the production of energy; molecules of carbon, hydrogen, and oxygen.

Hydrocarbons

Nonpolar chains of repeating hydrogen and carbon atoms.

Triglyceride

Formed from the synthesis of a glycerol backbone and $3$ fatty acids.

Phospholipid

A bond between the glycerol component of a lipid and a phosphorous molecule.

Protein

An organic molecule composed of amino acids linked by peptide bonds.

Amino acid

A molecule composed of an amine group and a carboxyl group with a variable side chain.

Peptide bonds

A covalent bond between two different amino acids.

Nucleotides

Composed of one or more phosphate groups, a pentose sugar (deoxyribose or ribose), and a nitrogen-containing base.

Deoxyribonucleic acid

Stores genetic information; double stranded.

Ribonucleic acid

Helps manifest genetic code as protein; single stranded.

Adenosine Triphosphate

High energy compound made of a ribose sugar, adenine base, and $3$ phosphate groups.

pH Scale

$0-14$; higher pH means fewer hydrogen atoms and lower pH means more hydrogen atoms.

DNA Nitrogenous Bases

Adenine, cytosine, guanine, and thymine.

RNA Nitrogenous Bases

Adenine, cytosine, guanine, and uracil.