Human digestive system

The body requires energy to perform activities. Which of the following nutrients is the main source of energy for the body?

• Carbohydrates

• Fats

• Fibres

• Proteins

It has been shown that animals restricted to a diet of milk only, eventually, suffer from blood disorders involving a risk of pigment in their red blood cells.

Which is the most likely explanation of this?

• Milk contains more calcium than is required by most animals.

• Milk is deficient in vitamin A.

• Milk is deficient in iron.

• Milk contains no roughage.

See the image carefully. Select the right answer describing the process shown in the image.

• Egestion

• Absorption

• Ingestion

• Assimilation

The presence of the villi in the small intestine increases the surface area for absorption of digested food

• True
• False

The Benedict's test is used to test the presence of starch and the positive result is the brick-red colour.

• True
• False

 The stomach’s wall secretes hydrochloric acid, which kills germs and provides an acidic pH environment for the proteases to work effectively.

• True
• False

________ digestion is the process of breaking down big pieces of food into smaller ones by either grinding, churning or emulsifying methods.

Peristalsis is a series of ________ muscle contractions that move food and fluids through the digestive system.

The image shows the different tissues and organs involved in the digestion of food. Provide detailed information on the different parts involved and what is their roles.

Explain the digestion of fats