AP BIOLOGY

Detailed explanation-1: -The correct answer is that most of the mass is breathed out as carbon dioxide and goes into thin air.

Detailed explanation-2: -The correct answer is that fat is converted to carbon dioxide and water. You exhale the carbon dioxide and the water mixes into your circulation until it’s lost as urine or sweat.

Detailed explanation-3: -As your body metabolizes fat, fatty acid molecules are released into the bloodstream and travel to the heart, lungs, and muscles, which break them apart and use the energy stored in their chemical bonds. The pounds you shed are essentially the byproducts of that process.

Detailed explanation-4: -Note that when a molecule of fat is consumed, all 55 carbon atoms in a fat molecule ends up in CO2, which we exhale out of the body. All of the 104 hydrogen atoms in a molecule of fat ends up in H2O, which is lost through sweating, urination, and exhalation.

Detailed explanation-5: -The researchers showed that during weight loss, 84 percent of the fat that is lost turns into carbon dioxide and leaves the body through the lungs, whereas the remaining 16 percent becomes water, according to the study published today (Dec. 16) in a special Christmas issue of the medical journal BMJ.