Top Ten Powerful Nations 2013 (According to Global Presence). Top Ten Powerful Countries Ranking (2012). NOTE: National Power Index (NPI) 2012 is a comprehensively revised version of the previous National Security Indexes published in Indiaâs National Security Annual Review (INSAR) series since 2002.op Ten Powerful Nations 2013 (According to Global Presence). Top Ten Powerful Countries Ranking (2012). NOTE: National Power Index (NPI) 2012 is a comprehensively revised version of the previous National Security Indexes published in Indiaâs National Security Annual Review (INSAR) series since 2002.
Overview. When you take in food, it's the job of your digestive tract to break that food down into smaller pieces through mechanical digestion, and then break larger molecules into smaller ones through chemical digestion.
As you continue chewing, your mouthful becomes sweet if you're eating carbohydrates because enzymes in your saliva begin to break complex carbs down into simple sugars. Later, in the stomach and intestines, proteins and fats are also broken down by enzymes.hemical digestion refers to the work performed by enzymes throughout your digestive tract, which break the bonds that hold molecules together so that proteins, carbohydrates and fats are split into single molecules.