digestive system

• What are the main processes of the digestive system?

  • Ingestion
  • Propulsion
  • Digestion (Mechanical and Chemical)
  • Absorption
  • Elimination
• What does ingestion refer to in the digestive system?

  The taking in of food into the alimentary canal
• What is the term for mixing and moving food within the digestive system?

  Propulsion
• How does the digestive system differentiate between mechanical and chemical digestion?

  • Mechanical digestion involves physical processes like chewing, mastication, and churning.
  • Chemical digestion involves enzymes and acids that break down food molecules.
• How are nutrients carried away from the intestines?

  Carried away by blood and lymph
• What process is responsible for the elimination of faeces from the digestive system?

  Defication
• What are the main organs of the digestive system?

  • Alimentary canal
  • Salivary glands
  • Pancreas
  • Liver
• What is another name for the alimentary canal?

  Alimentary tract
• From where to where does food pass through the alimentary canal?

  From mouth to anus
• What are the four basic layers of the alimentary canal from inside to outside?

  1. Mucosa – lining
  2. Submucosa
  3. Muscle layer
  4. Adventitia or serosa (outer cover)
• What is the name of the hollow tube within the alimentary tract?

  Lumen
• How is the muscle layer of the alimentary canal structured?

  It has two layers of smooth (involuntary) muscle: an outer longitudinal layer and an inner circular layer
• What are the two layers of peritoneum in the abdominal section?

  Parietal layer (lines the abdominal wall) and Visceral layer (covers the organs)
• What is peristalsis in the digestive system?

  Peristalsis is the alternating contraction and relaxation of muscle layers that propels food through the alimentary canal.
• What are sphincters in the digestive system?

  Sphincters are thickened areas of muscle that control the movement of food forward and backward, allowing for digestion and absorption.
• What structures are found in the submucosa layer of the alimentary canal?

  • Loose connective tissue
  • Blood vessels
  • Nerves
  • Lymph vessels and tissue
• What are the functions of blood vessels in the submucosa?

  They supply oxygen and carry away nutrients.
• What do nerves control in the submucosa layer?

  They control the functions of the digestive system.
• What do lymph vessels and tissue carry away in the submucosa?

  They carry away wastes, such as bacteria and cell debris.
• What are the three sections of the mucosa layer in the alimentary canal?

  1. Mucosa
  2. Lamina Propria
  3. Muscularis mucosa
• What type of tissue forms the lamina propria?

  Loose connective tissue
• What is the function of the lamina propria in the mucosa layer?

  It supports blood vessels and lymph vessels.
• What is the muscularis mucosa?

  It is a thin outer layer of muscle that provides involutions of the mucosal layer.
• What are the two main types of cells in the inner section of the mucosa layer?

  • Columnar epithelial cells
  • Mucus-secreting goblet cells
• What are the functions of columnar epithelial cells?

  They facilitate protection, secretion, and absorption.
• What glands produce gastric juice?

  Gastric glands
• What glands in the digestive system produce saliva?

  Salivary glands
• What glands produce intestinal juice?

  Intestinal glands
• Which organ produces pancreatic juice?

  Pancreas
• Which organ produces bile?

  Liver
• From which divisions of the autonomic nervous system are the nerves of the digestive system supplied?

  • Parasympathetic supply
  • Sympathetic supply
• What effect does the parasympathetic nervous system have on the digestive system?

  It causes muscle contraction and secretion of digestive juices.
• What nerves are responsible for the parasympathetic supply to the digestive system?

  The vagus nerves
• What effect does the sympathetic nervous system have on the digestive system?

  It reduces muscle contraction and glandular secretion.
• What are the components of the oral cavity?

  • Palate (roof of the mouth):
  • Hard palate (bone)
  • Soft palate (muscular) – prevents food entering nasal cavity
• What is the significance of the portal vein in the digestive system?

  The portal vein carries a high concentration of absorbed nutritional material to the liver.
• What forms the roof of the mouth?

  Palate
• What is the structure of the hard palate?

  Bone
• What is the structure of the soft palate?

  Muscular
• What function does the soft palate serve?

  It prevents food from entering the nasal cavity.