AP BIOLOGY

Detailed explanation-1: -Answer and Explanation: Our cells cannot use starch as it is. Before starch can enter a cell, it must be broken down into its individual glucose molecules. The glucose molecules can then be transported inside the cell and used to power cellular respiration reactions.

Detailed explanation-2: -When you eat starchy foods, the starches are broken down into sugars, including glucose, maltotriose and maltose, by an enzyme called amylase found in your saliva and small intestine. These compound sugars are further broken down into simple sugars by other enzymes, including maltase, lactase, sucrase and isomaltase.

Detailed explanation-3: -During digestion, starches and sugars are broken down both mechanically (e.g. through chewing) and chemically (e.g. by enzymes) into the single units glucose, fructose, and/or galactose, which are absorbed into the blood stream and transported for use as energy throughout the body.

Detailed explanation-4: -Why can’t a starch molecule enter a cell right after a person eats a meal with starchy foods in it? Because a starch molecule is too large to fit into a cell and needs to first be broken down into smaller glucose molecules in the digestive system.

Detailed explanation-5: -Glucose represents a monosaccharide, or simple sugar, with the chemical formula C6H12O6. Glucose is essential in living organisms because it serves as the primary reactant used in cellular respiration, in which a series of pathways produces ATP, the main energy source for cells.