Act 19: Vertebrates Digestive System

• Heterotrophs are divided into three groups based on their food sources: herbivores; carnivores; and omnivores.
• organization of the digestive systems vary according to the type food ingested by the organism: monogastric, avian, ruminant, and pseudo-ruminant.
• Vertebrates possess a complete digestive system which has two openings.
• mouth which is also called the oral or buccal cavity.
• Food is broken down mechanically in the mouth by the teeth which is the main organ of mastication.
• The chewed food becomes a rounded mass called a bolus.
• incisors - are used for biting, cutting and stripping of food.
• canines - are for seizing, piercing and tearing food
• premolars and molars - which are found in the back of the mouth (jaw) are for grinding and crushing of food.
• The act of swallowing or deglutition moves the bolus from the mouth to the stomach.
• Stomach 3 divisions: fundus, body, and pylorus.
• parts of small intestine: duodenum, jejunum, ileum
• Vili - folds of intestine for greater surface area
• Microvilli - intestinal walls of vili