the digestive system ch 24 notes

alimentary canal (aka gastrointestinal tract); accessory digestive organs

2 main features of the digestive system

mouth, pharynx, esophagus, stomach, small intestine, large intestine (SSLEMP)

organs of alimentary canal/gastrointestinal tract

30 ft long

how long is the alimentary canal for a cadaver?

surface area, swallowing

purpose of teeth is to increase __ _ and ease _

palatine and lingual tonsils

mouth/oral cavity contains these 2 structures:

skeletal muscles

walls of the pharynx has __ __ (that can be controlled) to initiate swallowing

10 in length

how long is esophagus

peristalsis

function of the esophagus is to push food down the stomach by __, the involuntary contraction and relaxation of muscles.

4 layers

esophagus contains the same _ _ as the stomach, small intestine, and large intestine

mucosa, submucosa, muscularis externa, serosa

the 4 layers of esophagus, stomach, s. intestine, and l. intestine

6-10 in. in length

stomach: how long is it?

Cardioesophageal sphincter

2

a volume equal to a gallon (think a gallon of milk)

3

Rugae

4 (large folds of collapsed mucosa)

Gastric juice

Stomach produces what juice?

Pepsin, hydrochloric ACID (HCI)

Chief cells produce __, while parietal cells produce __

Breakdown of protein

8

Chyme

9

Pyloric sphincter

10

Cardia, fundus, body, pylorus

Regions of stomach in order

Pyloric sphincter to ileocecal sphincter

2 sphincters (from start to end) of small intestine

Absorb food molecules

Function of small intestine

8-20 ft (96 - 240 in.)

How long is a small intestine?

2200 ft²

Surface area of the small intestine

Plicae circularis, villi, microvilli

3 features that increase the surface area for food absorption in the small intestine

Plasma membrane

What is the microvilli made of?

1 mm

How long is a villi

Plicae circulares

Large folded rings of small intestine’s inner lining

Digestive, bile

Pancreas make __ juice, while liver makes __

Through the duodenal papilla

How does the digestive juice and bile enter the small intestine?

Internal involuntary

Anus has external voluntary sphincter and _ _ sphincter

Taenia coli

Ribbons of muscle that run the length of colon

Haustra

Pocket-like sacs of colon