All AP Biology Resources
Example Questions
Example Question #11 : Understanding The Upper Digestive Tract: Mouth To Stomach
Parietal cells in the stomach secrete which of these?
Hydrochloric acid
Pepsin
Bile salts
Pepsinogen
Mucus
Hydrochloric acid
In the stomach, both hydrochloric acid and pepsinogen are secreted by gastric pits. Parietal cells in these pits secrete hydrochloric acid while chief cells in these pits secrete pepsinogen. Note that pepsinogen is inactive, and gets activated into pepsin via hydrochloric acid.
Example Question #12 : Understanding The Upper Digestive Tract: Mouth To Stomach
The esophagus is able to swallow liquids upside down, proving that swallowing is a process that does not depend on gravity. What is the name of this process?
esophageal emulsification
denaturation
peristalsis
salivation
flatulation
peristalsis
Peristalsis is the correct answer here. Peristalsis is the process of muscles contracting and relaxing in order to facilitate movement.
Example Question #13 : Understanding The Upper Digestive Tract: Mouth To Stomach
Removal of the gall bladder from the human body would most likely result in which of the following?
An inability to digest starch properly
An inability to digest proteins properly
An inability to digest fats properly
An inability to digest carbohydrates properly
An inability to digest fats properly
The gallbladder is found underneath the liver. The gallbladder is the storage place of bile, which helps to emulsify fats. Bile is necessary for the digestive system to break down fat. Removal of the gallbladder can result in fat malabsorption, which can present as loose stool.