Digestive system Flashcards
1
Q
other name for the digestive system
A
- gastrointestinal system
2
Q
four main functions of the digestive system:
A
- ingestion
- digestion
- absorption (mostly in the small intestine)
- elimination
3
Q
what is ingestion?
A
- food material taken into the mouth
4
Q
what is digestion?
A
- food is broken down, mechanically (chewing, stomach grinding) and chemically (acids, enzymes) as it travels through the GI tract
5
Q
what is absorption?
A
- digested food passes into the bloodstream through lining cells of the small intestine via villi
- nutrients travel to all cells of the body
- cells burn nutrients to release the energy stored in food
6
Q
what is elimination?
A
- the body eliminates solid waste materials that cannot be absorbed into the bloodstream
- the large intestine concentrates feces
- the wastes pass out of the body through the anus
7
Q
what is the digestive or gastrointestinal tract?
A
- tube that extends from mouth to anus
8
Q
what four layers of tissue make up the wall of the digestive tube?
A
- mucosa: type varies depending on location in the GI tract
- submucosa: connective tissue layer
- muscularis: circular, longitudinal and oblique (in stomach) layers of muscle important in GI motility
- serosa: serous membrane that covers the outside of abdominal organs
9
Q
what is peristalsis
A
- wavelike movement pushing food down the tract
10
Q
what is segmentation
A
- back and forth movement
11
Q
what is bolus
A
- ball of food (saliva + food)
12
Q
what is chyme
A
- bolus once it reaches the stomach and enters the slurry
13
Q
what is mastication
A
- chewing
14
Q
what is deglutition
A
- swallowing
15
Q
what is emulsification
A
- break down of fat, bile and enzymes
16
Q
organs of the digestive system:
A
- starts with the oral cavity
17
Q
what type of gland are salivary glands
A
- exocrine glands
18
Q
what are the 2 types of saliva
A
- serous type: watery and contains enzymes (salivary amylase - breaks down strach) but no mucus
- mucus type: thick, slippery and contains mucus but no enzymes - lubricates food during mastication
19
Q
what are the parotid glands and where are they found
A
- largest salivary glands, produce serous type saliva,
- located near the ear
20
Q
what are submandibular glands
A
- mixed gland: produce both serous and mucus type saliva
- located below mandibular angle
- ducts open on either side of lingual frenulum
21
Q
what are sublingual glands
A
- produce only mucus type saliva
- multiple ducts open onto floor of mouth below tongue
22
Q
3 anatomic components of the pharynx (throat)
A
- nasopharynx
- oropharynx
- laryngopharynx
23
Q
which of the 3 types of the throat are most involved in digestive processes?
A
- oropharynx
24
Q
what is the esophagus
A
- connects pharynx to stomach
- dynamic passageway for food
- food enters stomach by passing through lower esophageal sphincter / cardiac sphincter
25
what is a sphincter
- a ring of muscles
26
what is the function of the stomach and what are the 3 sections
- main grinding chamber composed of:
- fundus
- body
- antrum (where most of the grinding takes place)
27
what is rugae and what does it secrete
- ridges that line the inside of the stomach
| - secrete pepsin and hydrochloric acid
28
what sphincter separates the stomach from the small intestine
- pyloric sphincter
29
what are the 3 parts of the small intestine
1 - duodenum
2 - jejunum
3 - ileum
30
what are the 4 parts of the large intestine
```
1 - cecum
2 - ascending colon
3 - transverse colon
4 - descending colon
* also the sigmoid (sideways S shape) and rectum
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31
what is the liver in regards to the digestive system and what does it do to aid
the liver is an accessory organ
- helps maintain blood glucose levels
- manufactures blood proteins necessary for clotting
- releases bilirubin, a pigment in bile
- removes toxins and poisons from the blood
32
what is the gallbladder in regards to the digestive system and what does it do to aid
the gallbladder is an accessory organ
- located on the undersurface of the liver
- concentrates and stores bile made by the liver (bile is for emulsification of fat)
- common bile duct drains from hepatic/cystic ducts into the duodenum
33
what is the pancreas in regards to the digestive system and what does it do to aid
the pancreas is an accessory organ
- has a function in the endocrine system, endocrine functions (2% for insulin and glucagon), exocrine functions (98% for enzymes)
- exocrine functions: secretes pancreatic juices from pancreatic duct into the duodenum
enzymes: amylase (breaks down starch), lipase (breaks down fat), protease (breaks down proteins)
34
what is crohn's disease
- chronic inflammation of the intestinal tract
35
what is IBS
- irritable bowel syndrome: group of GI symptoms associated with stress ad tension (no structural abnormality)
36
what is ulcerative colitis
- chronic inflammation of the colon with the presence of ulcers
37
what is GERD
- gastroesophageal reflux disease
- heartburn
- improper closure of the lower esophageal sphincter
