There are a number of substances that the cell can use for energy in addition to carbohydrates. Proteins can be hydrolyzed to (1) ____________________ and then have the nitrogen group removed in a process called ____________________. Depending on the type of molecule in the (1) they will feed into either the end of glycolysis as ____________________ or feed into the ____________________. Lipids and fats are broken down into (2) ____________________. The b-oxidation of the molecules in (2) ultimately produces ____________________, which then enters at the beginning of ____________________ whose ultimate metabolic waste products are ______________________________ and ______________________________.