Biology Unit 5: The Chemistry of Life Flashcards
Matter
Anything that has mass and takes up space
Model
An explanation or representation of something that cannot be seen
Element
A collection of atoms that all have the same number or 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 Molecule
A molecule that contains only carbon and any of the following: hydrogen, oxygen, nitrogen, sulfur, and/or phosphorus
Biosynthesis
The process by which living organisms produce larger molecules from smaller ones
Isomers
Two different molecules that have the same chemical formula
Monosaccharides
Simple carbohydrates that contain 3 to 10 carbon atoms
Disaccharides
Carbohydrates that are made up of two 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, or molecules and surfaces repel water
Saturated fat
A lipid made from fatty acids that have no double bonds between carbon atoms
Unsaturated fat
A lipid made from fatty acids that have at least one double bond between carbon atoms
Peptide bond
A bond that links amino acids together in a protein
Hydrogen bond
A strong attraction between hydrogen atoms and certain other atoms (usually oxygen or nitrogen) in specific molecules
