Grade 9 Digestive System Revision

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

• To store food

• To break down food into smaller pieces

• To absorb nutrients

• To secrete digestive enzymes

Which enzyme in saliva helps break down carbohydrates?

• Amylase

• Pepsin

• Trypsin

• Lipase

What is the role of hydrochloric acid in the stomach?

• To absorb nutrients

• To create an acidic environment for enzymes

• To neutralize food

• To break down fats

What is the main function of the small intestine?

• Digestion of food

• Absorption of nutrients

• Storage of waste

• Production of enzymes

What is peristalsis?

• The movement of food through the digestive tract

• The process of breaking down food

• The secretion of digestive juices

• The absorption of nutrients

Which part of the digestive system is primarily responsible for water absorption?

• Small intestine

• Stomach

• Mouth

• Large intestine

What is the function of good bacteria in the gut?

• To create an acidic environment

• To produce digestive enzymes

• To absorb nutrients

• To break down food and release vitamins

What is the role of bile in digestion?

• To break down carbohydrates

• To emulsify fats

• To neutralize stomach acid

• To absorb proteins

Which nutrient cannot be synthesized by the body?

• Carbohydrates

• Fats

• Vitamins

• Proteins

What is the primary function of the duodenum?

• Mixing food with digestive juices

• Absorption of nutrients

• Breaking down proteins

• Storing waste