Biology A Unit 2: The Chemistry of Life Vocab

Surface Tension

The force that holds molecules together on the surface of liquid.

Monosaccharide

a simple sugar

Entropy

the randomness of any physical system

Fatty acids

Long chains of hydrocarbons that make up fats and phospholipids.

Activation Energy

The energy barrier that must be overcome for a reaction to occur.

Primary Structure

The order of amino acids that make up a protein or polypeptide

Amino Acids

The organic molecules that serve as the units from which proteins are made.

Covalent Bond

a bond in which electrons are shared between the bonded atoms.

polysaccharide

a carbohydrate composed of many simple sugar molecules bonded together in an unbranched or branched chains.

Disaccharide

a carbohydrate molecule composed of two monosaccharides bonded together.

Polypeptide

a chain of hundreds or thousands of amino acids

Hydrocarbon

a chemical composed entirely or primarily of carbon and hydrogen

Element

a chemical substance that contains only one kind of atom and that cannot be broken down into simpler substances

Starch

a complex polysaccharide that is formed from glucose subunits, found in grains and potatoes, and used for energy storage.

Glycogen

a complex, highly branched polysaccharide that is formed from glucose subunits, found in vertebrates, and used for energy storage.

Inorganic Compounds

a compound not formed from carbon-hydrogen bonds; more generally, a compound not produced by a living thing.

Peptide

a compound of two or more amino acids.

Lactose

a disaccharide sugar that is commonly found in milk; consists of galactose and glucose.

Sucrose

a disaccharide, with glucose and fructose subunits.

Hemoglobin

a large molecule that captures oxygen from the lungs and delivers it to the rest of the body.

Macromolecule

a large molecule, especially applied to carbohydrates, protein, lipids, and nucleic acids.

Chlorophyll

a molecule in plants that plays a key role in photosynthesis.

Polar Molecules

a molecule in which there are positive and negative areas.

Substrate

a molecule on which enzymes act.

Deoxyribose

a monosaccharide the sugar component of DNA.

Glucose

a monosaccharide with the chemical formula C6H12O6 used by cells for energy.

Ribose

a monosaccharide; the sugar component of RNA.

Neutron

a neutral particle with approximately the same mass as a proton, found in nuclei of atoms along with protons.

Adenine

a nitrogen-containing base that is part of one of the types of nucelotides that make up DNA or RNA; Pairs with thymine and uracil.

Guanine

a nitrogen-containing base that is part of one of the types of nucelotides that make up DNA or RNA; pairs with cytosine.

Cytosine

a nitrogen-containing base that is part of one of the types of nucelotides that make up DNA or RNA; pairs with guanine.

Thymine

a nitrogen-containing base that is part of one of the types of nucelotides that make up DNA; pairs with adenine.

Uracil

a nitrogen-containing base that is part of one of the types of nucelotides that make up DNA; pairs with adenine.

Proton

a positively charged particle found in the nuclei of atoms.

Enzyme

a protein that is a catalyst for chemical reactions in organisms; it increases the rate of the reaction without being used up or changed.

Solvent

a substance in which something is dissolved.

Catalyst

a substance present during a chemical reaction that speeds up the reaction but is not used up or changed during the reaction.

Solute

a substance that dissolves in solvent.

Nucleotide

a subunit of a nucleic acid that consists of a phosphate group, a five-carbon sugar, and a nitrogenous base.

Electron

a tiny part of an atom with a negative electrical charge

Atom

a tiny particle that is the fundamental building block of all substances and whose properties determine the properties of an element made up only of those atoms.

Ion

an atom that has a positive or negative electrical charge.

Cohesion

an attraction between molecules of the same substance.

Cellulose

an unbranced polysaccharide formed from glucose subunits, found in plant cell wall, used for structural support.

Organic Compound

any chemical compound that contains carbon bonded to at least one other atom, usually hydrogen.

Organic Compounds

any chemical compound that contains carbon bonded to at least one other atom, usually hydrogen.

Molecule

any compound resulting from covalent bonding.

Matter

anything that takes up space and has mass; the three usual forms of matter are solid, liquid, and gas.

Nitrogenous

containing nitrogen.

DNA

deoxyribonucleic acid; this is the molecule, unique to each individual, carrying the genetic information to be found in every cell; all the information an organism needs to live and reproduce is contained in DNA.

Lipid

fats, oils, phospholipids, steroids, and waxes; one of four major classes of large organic molecules.

RNA

ribonucleic acid; nucleic acid that used the instructions stored in DNA to build proteins.

Quaternary Structure

the association of two or more polypeptide chains in a spatial relationship to make up a protein.

Secondary Structure:

the coiling or folding of a polypeptide in which amino acids near one another in the chain bond.

Valence Electrons

the electrons in any atom's outer level.

Tertiary Structure

the folding of a polypeptide with secondary structure in which amino acids far apart from one another in the chain bond.

Ionic Bond

the force of attraction between a charged atom (or group of connected atoms) and another with the opposite charge.

Hydrogen bond

the force of attraction between a partially charged atom and a hydrogen atom that is covalently bonded to another partially charged atom.

amino acids

the organic molecules that serve as the units from which proteins are made.

Active Site

the place on an enzyme where the substances attach and the reaction occur.

Photosynthesis

the process by which plants and certain other organisms use the energy of sunlight to convert carbon dioxide and water into sugar and oxygen.

Hydrophobic

water hating; not soluble in water.

Hydrophilic

water loving; soluble in water.

Aqueous

watery

Adhesion

An attraction between the molecules of one substance and the molecules of another substance.

Bioluminescence

light produced by a living organism.

Proteins

one of four major classes of large organic molecules, made of amino acids.

Nucleic Acids

one of four major classes of large organic molecules, which are important in storing, transmitting, and making useful the information necessary for the processes of life.

Carbohydrates

one of the four major classes of large organic molecules made from carbon, oxygen, and hydrogen.