Matter
Anything that has mass and takes up space
model
explanation or representation of something that cannot be seen
Element
A collection of atoms that all have the same number of protons.
Molecules
Chemicals that result from atoms linking together
physical change
A change that affects the appearance but not the chemical makeup of a substance.
chemical change
A change that alters the makeup of the elements or molecules of a substance.
phase
One of the three forms--solid, liquid, or gas--which every substance is capable of attaining.
Diffusion
The random motion of molecules from an area of high concentration to an area of low concentration.
Concentration
A measurement of how much solute exists within a certain volume of solvent
semipermeable membrane
A membrane that allows some molecules to pass through but does not allow other molecules to pass through.
Osmosis
The tendency of a solvent to travel across a semipermeable membrane into areas of higher solute concentration.
catalyst
A substance that alters the speed of a chemical reaction but is not used up in the process.
organic molecules
A molecule that contains only carbon and any of the following: hydrogen, oxygen, nitrogen, sulfur, and/or phosphorous.
Isomers
Two different molecules that have the same chemical formula
Monosaccharides
Simple carbohydrates that contain 3 to 10 carbon atoms.
Dissacharides
Carbohydrates that are made up of two or more monosaccharides
Polysaccharides
Carbohydrates that are made up of more than two monosaccharides
dehydration reaction
A chemical reaction in which molecules combine by removing water
Hydrolysis
Breaking down complex molecules by the chemical addition of water
Hydrophobic
Lacking any affinity to water.
saturated fats
A lipid made from fatty acids that have no double bonds between carbon atoms
unsaturated fats
A lipid made from fatty acids that have at least one double bond between carbon atoms.
peptide bond
Bonds that connect amino acids.
hydrogen bond
A strong attraction between hydrogen atoms and certain other atoms (usually oxygen or nitrogen) in specific molecules.
Biosynthesis
The process by which living organisms produce larger molecules from smaller ones.