Nokea
Which of these organs is not considered an accessory digestive structure?
Correct Answer: A
Rationale: The correct answer is A: mouth. The mouth is not considered an accessory digestive structure because it is part of the main digestive system. The mouth is where the process of digestion begins with the mechanical breakdown of food through chewing and the chemical breakdown through the action of saliva produced by salivary glands. The salivary glands, pancreas, and liver are all accessory digestive structures because they aid in the digestion process but are not part of the alimentary canal. Salivary glands produce enzymes to further break down food, the pancreas secretes digestive enzymes and bicarbonate into the small intestine, and the liver produces bile to aid in the digestion and absorption of fats. These organs work alongside the main digestive system to help with the breakdown and absorption of nutrients.