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Nutrition in Animals: Dentition and Digestion

<h3>Heterotrophic nutrition</h3><p>Animals are <strong>heterotrophs</strong> &mdash; they feed on food made by other organisms. To use this food, the body must break it down into small soluble particles through <strong>digestion</strong>, which is both physical (chewing) and chemical (enzymes).</p><h3>Types of teeth (dentition)</h3><ul><li><strong>Incisors</strong> &mdash; chisel-shaped, for biting and cutting.</li><li><strong>Canines</strong> &mdash; pointed, for tearing and holding food.</li><li><strong>Premolars and molars</strong> &mdash; broad with ridges, for grinding and chewing.</li></ul><h3>The journey of food</h3><p>Digestion starts in the <strong>mouth</strong>, where teeth and saliva work on the food. It continues in the <strong>stomach</strong> with acidic gastric juice, then in the <strong>duodenum</strong> and <strong>ileum</strong> where bile and pancreatic juice complete the job. The digested nutrients are absorbed in the <strong>ileum</strong>, which is adapted with a long length, many folds and millions of finger-like <strong>villi</strong> that increase surface area for fast absorption.</p><div class="callout"><strong>Kenyan context:</strong> A balanced Kenyan plate of ugali, beans and managu gives carbohydrates, proteins and vitamins. The teeth and digestive enzymes break these down so the body can absorb the nutrients &mdash; and brushing twice a day keeps those important grinding molars healthy.</div>
Audio narration — reads aloud, works offline

Animals that feed on food made by other organisms are called: