Week 24 Flashcards
(25 cards)
What are the main components of the digestive system?
- Mouth
- Oesophagus
- Stomach
- Small intestine
- Large intestine
- Accessory organs (teeth, tongue, salivary glands, liver, gallbladder, pancreas)
What is the primary function of the digestive system?
To break down food into molecular size for absorption and use by cells
How long is the GI tract?
Approximately 8 meters long
What are the four distinct layers of the GI tract?
- Mucosal layer
- Submucosal layer
- Muscularis layer
- Serosa layer
What is the role of the peritoneum?
- Visceral layer covers organs
- Parietal layer lines the walls of body cavities
- Peritoneal cavity contains serous fluid
Where does digestion begin?
In the mouth
What are the three types of salivary glands?
- Parotid
- Submandibular
- Sublingual
What is the function of saliva?
- Moistens food
- Dissolves food for tasting
- Buffers acidic foods
- Starts chemical digestion of starch
- Contains enzymes that help destroy bacteria
What are the main structures of a tooth?
- Crown
- Neck
- Roots
- Pulp cavity
What are the primary and secondary dentitions?
- Primary teeth: 20 (0.5 - 4 years)
- Secondary teeth: 32 (6 years onwards)
What is the length of the oesophagus?
25 cm long
What are the two phases of swallowing?
- Voluntary phase
- Involuntary phase
What is the stomach’s shape and capacity?
J-shaped enlargement with at least 1L capacity
What is the function of rugae in the stomach?
Allows the stomach to stretch
What are the three layers of smooth muscle in the stomach’s muscularis?
- Outer longitudinal
- Circular
- Inner oblique
What does the pancreas secrete?
- Na bicarbonate
- Digestive enzymes (pancreatic juice)
What components does bile contain?
- Water
- Cholesterol
- Bile salts
- Bile pigments (bilirubin)
What are the three parts of the small intestine?
- Duodenum
- Jejunum
- Ileum
What is the role of villi in the small intestine?
Contains vascular capillaries and lacteals for absorption
What is the length of the large intestine?
5 feet long
What are the subdivisions of the large intestine?
- Cecum
- Colon
- Rectum
- Anal canal
What is defecation?
The elimination of faeces from the rectum
True or False: The external anal sphincter is under voluntary control.
True
Fill in the blank: The stomach converts a bolus to a liquid called _______.
chyme
