What is digestion?
What is metabolism?
- regulation of cellular activities
What are two functional groups of organs?
- accessory digestive organs
Structures of alimentary canal
mouth pharynx esophagus stomach small intestine large intestine anus
Structures of accessory organs
salivary glands
liver
gall bladder
pancreas
6 functions of salivary glands
Mastication
Types of teeth
How many teeth do we have?
- 20 primary deciduous (baby) 32 secondary (permanent)
Deglutition
what does this involve
swallowing
Mouth, pharynx, upper esophagus muscles are innervated by
somatic motor neurons
Middle and lower esophagus muscles are innervated by
autonomic neurons
What is the esophagus
What is peristalsis?
food moves by a wave like muscular contraction (involuntary control) so it doesnt come out
- peristaltic contraction
The stomach has ____ muscle layers
smooth muscle layers
What direction do the muscles of the stomach run
Why are the muscles of the stomach arranged perpendicularly?
- mix and mechanically break up food in stomach
What does the mucosal region of the stomach contain?
- gastric glands
What are gastric pits?
What do the gastric glands consist of (cells)?
from top to bottom:
- mucous cell
parietal cell
- chief cell
What doe mucous cells secrete?
mucus
What doe parietal cells secrete?
HCl, intrinsic factor (B12 - essential for life)
What doe chief (zymogenic) cells secrete?
pepsinogen
Why can’t the stomach digest itself
mucousal layer protection