Digestive System Metabolism Quiz

Extracellular and Cellular Metabolism in Digestive System

• Ingested food is broken down into smaller molecules in the digestive system through extracellular metabolism
• Gastrointestinal (GI) system consists of GI tract and accessory organs, including mouth, esophagus, stomach, small and large intestines, pancreas, salivary glands, liver, and gallbladder
• Digestive activities in the lumen of GI tract are referred to as "extracellular" metabolism as it is continuous with the outside environment
• Starch digestion starts in the mouth by amylase and continues in the upper part of the stomach, then fully digested in the small intestine
• Monosaccharides like glucose and fructose are absorbed into the body across the epithelial cells lining the villus and then enter the blood
• Extracellular metabolism of dietary proteins begins in the stomach, where pepsin unfolds and cleaves peptide bonds, further cut in the small intestine
• Fats are processed and transported differently due to their insolubility in aqueous mediums, emulsified into smaller droplets in the small intestine
• Emulsified droplets of fat are digested by lipase into fatty acids and monoglycerides, then recombined into triglycerides in intestinal epithelial cells
• Over 8 liters of water enters the GI tract to digest less than 1 kg of food, with 99% being absorbed back into the blood
• Water is needed to hydrolyze monomeric or dimeric units of each macromolecule during digestion
• The digestive system consists of complex processes for the breakdown and absorption of nutrients from ingested food
• The extracellular and cellular metabolism in the digestive system involves numerous enzymes, organs, and mechanisms for the breakdown and absorption of macronutrients.

Test your knowledge of extracellular and cellular metabolism in the digestive system with this quiz. Explore the processes of breaking down and absorbing nutrients from ingested food, involving enzymes, organs, and mechanisms.