Digestive System Functions and Processes

This video tutorial covers Cambridge IGCSE Biology topic 7.3 on physical digestion. It explains the breakdown of food without chemical changes, focusing on the role of human teeth and the stomach. The structure of a human tooth is detailed, and the extended section covers bile's role in emulsifying fats. The lesson follows the Cambridge syllabus closely, preparing students for their final exam.

What is the primary purpose of physical digestion?

• To chemically alter food molecules

• To eliminate waste products from the body

• To increase the surface area of food for enzyme action

• To absorb nutrients directly into the bloodstream

Which type of teeth are primarily used for cutting food?

• Canines

• Molars

• Premolars

• Incisors

What is the primary role of canines in the mouth?

• To store food

• To grind food

• To cut food

• To tear food

What is the function of the enamel on a tooth?

• To supply nutrients to the tooth

• To protect the inner components of the tooth

• To anchor the tooth to the jaw

• To produce saliva

What is the role of the pulp cavity in a tooth?

• To store food particles

• To produce enamel

• To contain blood vessels and nerve cells

• To grind food

Which part of the tooth is responsible for anchoring it to the jaw?

• Pulp cavity

• Enamel

• Dentine

• Cement

How does the stomach contribute to physical digestion?

• By filtering toxins

• By producing bile

• By absorbing nutrients

• By churning and mixing food with gastric juice

Which of the following is NOT a function of the stomach in digestion?

• Churning food

• Breaking down food into a liquid

• Absorbing nutrients

• Mixing food with gastric juice

What is the main function of bile in digestion?

• To digest proteins

• To emulsify fats into smaller droplets

• To break down carbohydrates

• To neutralize stomach acid

Where is bile stored before it is released into the duodenum?

• In the liver

• In the pancreas

• In the gallbladder

• In the stomach