The digestive system has 3 main functions Breaks
The digestive system has 3 main functions: • Breaks down food into molecules • Absorption of food molecules into the blood • Elimination of waste from the body There are 2 kinds of digestion: • Mechanical – food is broken down into smaller pieces • Chemical – food is broken down into molecules
Where do mechanical and chemical digestions begin? What organ carries out mechanical digestion by breaking down food into smaller pieces of food? What wets the food and chemically breaks down starches into simple sugars with the help of enzymes? What do we call the food inside the mouth? Saliva. Bolus. In the mouth. The teeth.
At the back of the mouth there are 2 openings: • Windpipe • Esophagus – lined with mucus How long does it take for food to reach the stomach? 10 seconds. What do we call the muscle contractions that push the food down to the stomach. Peristalsis.
Both mechanical and chemical digestions take place in the stomach. Mechanical digestion mixes food with fluids. Chemical digestion happens when pepsin breaks down protein into short chains of amino acids with the help of hydrochloric acid (HCl). HCl also kills harmful bacteria.
Where does most of chemical digestion take place? In the small intestine. Absorption of carbohydrates, proteins and fats takes place in the small intestine.
Villi that cover the inside of the small intestine absorb the finally digested nutrients into the blood.
What does liver produce? Bile that breaks down fats into smaller fat droplets.
What does pancreas produce? It produces enzymes that flow into the small intestine and break down starches, proteins and fats.
What is absorbed in the large intestine? Water is absorbed into the blood. The digestive system ends in rectum and anus.
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