Digestion breaks food down into tiny pieces the body can use. It starts in the mouth, where teeth chop and grind the food and saliva makes it wet. You swallow, and the oesophagus (food pipe) pushes the food to the stomach. The stomach churns it with acid. In the small intestine the useful parts pass into the blood. The large intestine takes back water, and the waste leaves the body.
Humans have different teeth for different jobs. Incisors at the front cut and bite. Canines are pointed and tear food. Molars at the back are wide and flat for grinding. Brushing twice a day and eating fewer sugary foods help stop tooth decay.
Worked example
Where does most digested food pass into the blood?
- After the stomach, food goes to the small intestine.
- Its walls let tiny food pieces pass into the blood.
Answer:So it is the small intestine.
Key words
- digestion
- breaking food down so the body can use it
- stomach
- a stretchy bag where food is churned with acid
- small intestine
- where food passes into the blood
- molars
- wide back teeth for grinding
New questions every time.
NGSS-referenced: 4-LS1-1