The Digestive System: CrashCourse Biology #28

What is the primary function of the digestive system?

• To circulate blood throughout the body

• To break down food and absorb nutrients

• To control body temperature

• To produce hormones for growth

How do the digestive systems of dogs and cows differ based on their diets?

• Dogs have a long digestive tract to process plants, while cows have a short one for meat.

• Dogs have a short digestive tract for quick processing of meat, while cows have a long one with multiple stomachs for plant digestion.

• Both dogs and cows have similar digestive systems because they are both mammals.

• Dogs rely on microorganisms for digestion, while cows use strong stomach acids.

Why is chewing food thoroughly important for human digestion?

• It helps to cool down the food before swallowing.

• It increases the surface area of the food for enzymes and acids to work on.

• It prevents food from getting stuck in the throat.

• It adds essential vitamins to the food.

What feature of the human small intestine helps maximize nutrient absorption?

• Its thick muscular walls.

• Its short length, allowing quick passage of food.

• Its large surface area due to folds and absorbing fibers.

• Its ability to produce strong digestive acids.

What is the function of the epiglottis during swallowing?

• To break down food into smaller pieces

• To push food down the esophagus

• To prevent food from entering the windpipe

• To mix food with digestive juices

Which of the following is a primary component of gastric juice in the stomach?

• Bile

• Saliva

• Hydrochloric acid

• Bicarbonate

What structures in the small intestine greatly increase its surface area for nutrient absorption?

• Rugae

• Sphincters

• Villi and microvilli

• Cecum

What is the main role of the large intestine in the digestive process?

• To break down proteins into amino acids

• To absorb most of the nutrients from food

• To reabsorb water and bile salts from undigested food

• To produce gastric juice