Stomach versus Small Intestines

Which organ is responsible for the initial breakdown of proteins?

• Large intestines

• Small intestines

• Pancreas

• Stomach

Answer explanation

The stomach is responsible for the initial breakdown of proteins through the action of gastric juices, which contain pepsin, an enzyme that begins protein digestion.

What is the role of the small intestines in digestion?

• To store food temporarily

• To produce digestive enzymes

• To absorb nutrients and minerals

• To initiate protein digestion

Answer explanation

The small intestines play a crucial role in digestion by absorbing nutrients and minerals from the food we eat, making this the correct answer. While they also produce enzymes and initiate protein digestion, absorption is their primary function.

How does the stomach protect itself from its own acidic environment?

• By neutralizing acids with enzymes

• By secreting a thick mucus layer

• By rapidly absorbing acids

• By producing bile

Answer explanation

The stomach protects itself from its acidic environment by secreting a thick mucus layer. This mucus acts as a barrier, preventing the acid from damaging the stomach lining.

Which organ is primarily responsible for nutrient absorption?

• Liver

• Small intestines

• Stomach

• Large intestines

Answer explanation

The small intestines are primarily responsible for nutrient absorption. They have a large surface area due to villi and microvilli, which facilitate the absorption of nutrients from digested food, unlike the liver, stomach, or large intestines.

What is the primary function of the stomach in the digestive system?

• To produce bile for fat digestion

• To store waste before elimination

• To absorb nutrients into the bloodstream

• To break down food using acids and enzymes

Answer explanation

The primary function of the stomach is to break down food using acids and enzymes. This process prepares food for further digestion and nutrient absorption in the intestines, making it the correct choice.