3. The Molecules of Life Flashcards
organic compounds
The study of carbon-based molecules.
functional groups
Groups of atoms directly involved in chemical reactions.
macromolecules
Gigantic molecules like carbohydrates, proteins, and nucleic acids.
polymers & monomers
Polymers are large molecules made by stringing together manysmaller molecules called monomers
dehydration reaction
For each monomer added to a chain, a water molecule (H 2 O) is formed by the release of two hydrogen atoms and one oxygen atom from the reactants.
hydrolysis
The breakdown of polymers occurs by hydrolysis. Cells break bonds between monomers by adding water to them, a process that is essentially the reverse of a dehydration reaction.
carbohydrates
A class of molecules that includes sugars and polymers of sugars.
monosacchrides
The monomers of carbohydrates; they cannot be broken down into smaller sugars.
isomers
Molecules that have the same molecular formula but different structures.
disaccharide
Constructed from two monosaccharides by a dehydration reaction.
polysaccharides
Long chains of sugars— poly mers of mono saccharides.
starch
Consists of long strings of glucose monomers. Starch granules serve as carbohydrate “storage tanks” from which plant cells can withdraw glucose for energy or building materials.
glycogen
Animals store excess glucose in the form of a polysaccharide. Glycogen is a polymer of glucose monomers, but glycogen is more extensively branched. Most of your glycogen is stored in liver and muscle cells, which break down the glycogen to release glucose when you need energy.
cellulose
The most abundant organic compound on Earth, forms cable-like fibrils in the tough walls that enclose plant cells and is a major component of wood and other structural components of plants.
Unlike the glucose linkages in starch and glycogen, those in cellulose cannot be broken by any enzyme produced by animals.
hydrophilic
Molecules that dissolve readily in water.
