Lab 14 Digestive System Flashcards
What are the 2 main components of the digestive system?
- Digestive Tract
- Accessory Organs
What are all the accessory organs?
teeth, tongue, salivary glands, liver, gall bladder, pancreas
What are the gums called?
Gingiva
What are the functions of the tongue?
food manipulation, taste, speech
What is the process of teeth breaking down food?
Mastication
What are the function of inisors?
cutting and shearing foods
What type of tooth tears food with a single cusp?
Canine
How many cusps for premolars have?
2
What are the function of molars?
Grinding food into small pieces
How many teeth are in the average adults mouth?
32
How many teeth are in a child mouth with deciduous teeth?
20
What are the 2 principal parts of a tooth?
Crown: exposed portion of the tooth
Root: imbedded in the alveolus (bony socket) of the maxilla and mandible
What are the 3 pairs of salivary glands and where are they located?
1) Parotid Gland; largest, anterior to the ear
2) Submandibular Glands; inner surface of the mandible
3) Sublingual Gland; anterior and deep to the submandibular glands
What do the salivary glands secrete?
Saliva
What does saliva contain and how does it aid in digestion?
Enzyme: salivary amylase
- begins the digestion of carbohydrates
What are the functions of saliva?
- Lubricating the mouth
- Moisten food
- Dissolve chemicals in food so they can be tasted
What are the 3 sections of the pharynx?
- nasopharnyx
- oropharynx
- laryngopharynx
Which 2 regions of the pharynx are involved in the digestive system?
oropharynx and laryngopharynx
What structure closes of the larynx so foods and fluids do not enter the respiratory tract?
epiglottis
Where does chemical digestion begin?
Stomach
Where is chemical digestion completed in the body?
Small Intestine
In order what are the 3 regions of the small intestine
Duodenum, Jejunum, Ileum
Which region of the small intestine receives secretions from the pancreas, liver and gall bladder?
Duodenum
Where does absorption of nutrients begin in the digestive tract ?
Small Intestine
What is the major function of the large intestine?
Absorption of water from undigested food material
What are the 3 accessory organs within the abdominal cavity?
Gall Bladder, Liver, Pancreas
What is the digestive function of the liver?
To produce and secrete bile.
What are the lobes of the liver called and what are their shape?
Hexagonal, lobules
What is the function of the gall bladder?
Store and concentrate bile.
How does the pancreas aid in digestion within the duodenum?
Secretory cells produce pancreatic juice which contains many important enzymes
What is the function of the fluid produced by the peritoneum?
Combine the digestive organs to the abdominopelvic cavity, lubricate and protect the organs.
What are the 3 layers of the esophagus?
- Mucosa: inner layer
- Submucosa: middle layer filled of blood vessels and nerves
- Muscularis: external layer of longitudinal muscle
What type of epithelium comprises the mucosa of the esophagus?
stratified squamous epithelium
What is the major movement in the digestive tract?
Peristalsis
What type of epithelium is common to the stomach, small intestine, and large intestine?
Simple columnar epithelium
What is distinctive to the tissues of the stomach?
Gastric Pits
What are the 3 layers of the Muscularis layer of the stomach?
- Oblique Muscle
- Circular Muscle
- Longitudinal Muscle
Are goblet cells visible in the small intestine?
Yes.
What is distinctive to the histology of the small intestine?
Villi
Why are goblet cells so abundant in the large intestine?
Because they produce mucin which absorbs water.
Define automaticity.
The ability to contract without nervous stimulation.
What is rhythmicity?
A regular pattern of repeated contractions.
What is the role of the autonomic nervous system in visceral smooth muscle regarding the GI tract?
To regulate the rate and he relative strength of contraction.
What 2 characteristics of visceral smooth muscle are responsible for peristalsis?
Automaticity and Rhythmicity
