Test your knowledge of the digestive system with these advanced, application-based questions.
Read the following scenario and answer the questions:
Scenario: During a science experiment, a student takes a piece of plain bread and chews it continuously for three minutes without swallowing. Initially, the bread tastes plain and starchy, but after a few minutes of chewing, it begins to taste distinctly sweet.
Q1. Explain the biological reason behind the change in the taste of the bread. What specific substance in the mouth is responsible for this?
Q2. If the student had swallowed the bread immediately without chewing, how would it affect the rest of the digestive process in the stomach?
Q3. The inner walls of the small intestine are highly folded and covered with millions of tiny finger-like projections called villi. What is the functional advantage of having these villi instead of a smooth inner wall?
Q4. A patient has their gallbladder surgically removed due to gallstones. The gallbladder's job is to store bile produced by the liver. Based on your knowledge of digestion, what dietary changes should the doctor recommend to this patient and why?
Directions: For the following questions, a statement of Assertion (A) is followed by a statement of Reason (R). Choose the correct option:
Q5.
Assertion (A): The stomach secretes strong hydrochloric acid (HCl) during digestion.
Reason (R): The acid helps to neutralize the food, making it alkaline so that stomach enzymes can function.
Q6.
Assertion (A): The large intestine is responsible for absorbing water from undigested food.
Reason (R): Once nutrients are absorbed in the small intestine, the remaining liquid waste passes into the large intestine, where water is reabsorbed to form solid feces.
Q7. Ruminants (like cows) can easily digest cellulose present in grass, while humans cannot derive any energy from eating grass. Explain the anatomical and biological difference in the digestive systems of cows and humans that causes this.