AP BIOLOGY

Detailed explanation-1: -Carbohydrates are the nutrients most frequently used as an energy source (containing 4kcal per gram), as they are fast-acting and turn into energy as soon as they are ingested. This energy powers the brain and body. The energy that powers the brain and body is generated when carbohydrates are broken down.

Detailed explanation-2: -The food items rich in carbohydrates and fats provide a quick source of energy. A very common example of such food is glucose. The glucose decomposes in presence of oxygen to produce a significant amount of energy accompanied by water and carbon dioxide.

Detailed explanation-3: -Complex carbohydrates are made up of lots of sugars combined together. Sources of complex carbohydrates that will give you long-lasting energy include whole grains, fruits and vegetables. Popcorn, brown rice, wild rice, quinoa, barley, oatmeal, bulgur and buckwheat are examples of whole grains.