The Digestive System Flashcards
How long is the digestive system in adults?
29 ft
8.4 metres
Give 3 accessory organs in the digestive system
Teeth Tongue Salivary glands Liver Pancreas Gall bladder
What are the 4 main layers of the digestive system
Mucosa
Sub mucosa
Muscularis
Serosa
What are the 3 layers of the mucosa and their roles
Epithelium- protects against scratches in mouth and oesophagus and secretes and absorbs in stomach and lower intestine
Lamina proparia- protects against bacteria
Muscularis mucosa- smooth muscle
What is the role of the submucosa
It contains nerves, brigs a blood supply to the system and contains glands
What is the Muscularis
Layers of muscle that pulsate
Linked to the autonomic nervous system
What is the serosa
Connective tissue that secretes liquid preventing fiction
Explain the role of the mouth in digestion
Taste buds stimulate salivary glands
Teeth firing tear shred and chew
Tongue shapes food into bolus
Amylase breaks down starch and lubricates food
Howling does it take for food to reach the stomach
6 seconds
What are the 3 sections of the stomach
Fundus- at the top near the oesophageal sphincter
The body
The Antrim- contains pyloric sphincter
What are the four cells in the stomach
Goblet cells- make mucus that protects from acid
Parietal cells- release heck and intrinsic factor
G cells- secrete gastric which controls acid
Chief cells- release pepsinogen which is converted to pepsin by Hcl
What is intrinsic factors use in the stomach
Helps the absorption of b12 and the production of red blood cells
What are 5 major components of the digestive system
Mouth Pharynx Oespohagus Stomach Small intestine Large intestine Rectum and anal canal
