Download AP Digestive System Guided Notes

Anatomy and Physiology Digestive System Guided Notes
Jenna, Nicole, Billy, Carlos, Charline
The function of the digestive system is _____________________________ and ___________________________.
Digestion is the breakdown of food into small molecules, which are then _______________________into the
body. The digestive system has two openings - the _________________ and the _________________.
Mouth
 Receives food and begins ____________________ by cutting the food into pieces (____________________
digestion) and mixes it with saliva (_____________________________ digestion)
 Saliva consists of 4 enzymes :
o __________________________________ : breaks down starch → releases maltose sugar molecules
o Lysozyme secretion : breaks down carbohydrates in cell walls of bacteria that are coming in
o Lingual lipase : breaks down fat and Salivary Kallikrein : breaks down very specific proteins
Salivary Glands
 Saliva _____________________
 _____________________ food
 Binds the particles
 Initiates ____________________________ digestion of carbohydrates
 Aids in cleansing mouth and teeth
 2 cell types in secretion: serous and mucous
 ______________________ produce watery fluid with digestive enzyme amylase
 ____________________ produce thick liquid mucus binding food and assisting in swallowing
smoothly
 ____________________________ nervous system releases salvia when sense something pleasing about
food
________________________
 Posterior cavity that connects _________________________ with esophagus
 Doesn’t digest food, but is used for ___________________________
 Structure : (from top to bottom)
 Nasopharynx
 Oropharynx
 Laryngopharynx
 Swallowing has 3 stages:
 Food is chewed and mixed with saliva, tongue rolls it into a mass (___________________)
 Food stimulates sensory ________________________ → triggers swallowing ______________
 ___________________________ transports food to the stomach
Esophagus
 The esophagus is a muscular __________________ connecting the throat with the _________________.
 The upper esophageal sphincter is a bundle of muscles on top of the esophagus the UES are under
conscious control like when breathing, eating, belching, and vomiting. They keep food and secretions
from going down the _______________________.
 The lower esophagus sphincter also has bundle of muscles. When the LES is closed it prevents
_________________ and stomach contents from traveling back up the esophagus.
 The LES is not under conscious control.
Stomach
The ________________________________ is a muscular organ that’s located on the left side of the upper
abdomen. The stomach’s function is to
 Expand to temporarily ____________________ food.
 Churning the stomach muscles so that it physically ________________ _______________the food.
 releases ___________________ and ___________________ for the chemical breakdown of food.
 The stomach releases food into small _________________________in a controlled and regulated manner.
Small Intestine
The small intestine is only about as big around as a _____________________ finger. The small intestine is a
muscular tube with _________________ parts. These parts work together to provide the following functions of
the small intestine:
 The ____________________________ breaks down the food.
 The _______________________and the ______________________absorb nutrients and send them into the
bloodstream
 The inner lining of the small intestine is folded back and forth to increase _______________ ___________
for better nutrient absorption.
 These folds create microscopic finger-like projections that are called _________________________.
 Over ___________percent of ingested carbohydrates and proteins are absorbed here
Liver
A healthy liver does the following
 Regulates the composition of _______________________ (amounts of sugar, also known as glucose,
protein, and the fat that enters the bloodstream.)
 Removes ______________________________ from the blood.
 Processes the nutrients absorbed by the intestines during digestion, converts them into forms that can
be used by the body.
 Stores nutrients such as _________________________, ____________________, and other minerals.
 Produces ____________________ factors, which are the chemicals needed to help blood clot.
 Breaks down (metabolizes) ______________________________ and many drugs.
 Creates ________________________
Pancreas
 Part of digestive and ____________________________ system
 Associated with small intestines
 Secretes “pancreatic juice”
 Produced by cells - “pancreatic acinar”
 Cluster and release
 Contain ___________________________ digesting carbohydrates, fats, nucleic acids, and proteins
 Released into ___________________________
Gallbladder
 “___________________-shaped sac on liver’s inferior surface”
 Important in digesting ___________________ correctly
 Receives ____________________ created by liver
 Concentrate the bile and blend with salts and enzymes
 Releases to small intestines
 Connects to cystic duct (joining common hepatic duct)
 Forms __________________________ bile duct
 Lined with ______________________________ cells
Large Intestines
1. The intestine is an extended, tube running from the end of the stomach to the anus.
2. The intestines include the small intestine, large intestine, rectum.
3. The large intestines are the final stages of digestion.
4. Its task is to ____________________ nutrients and ________________________while converting ingested
food into ____________________________.
Rectum and Anus
 Final sector of the digestive system, performing the act of _____________________________, or ridding
the body of waste



After being produced by the rest of the digestive system, stool moves from the ____________________
colon into the rectum
_______________________________informs the body that stool needs to be passed
The _______________________, the opening through which the stool passes, remains closed by the anal
____________________________ until the passing of stool is initiated by the person, and then widens
How the digestive systems helps to maintain homeostasis:
 Maintains homeostasis by breaking food down into a _____________________ form that can be taken in
by the body.
 Works closely with _______________________________ system
 __________________________________ absorbed nutrients throughout body
 Works with _________________________________ system
 Intake of _________________________________ - absorbing calcium from food particles
 Works with lymphatic system
 Absorbs ____________________ and fat-soluble vitamins from digestive system
Label the Digestive system below using the word bank
Anus
Pancreas
Pharynx
Gallbladder
Esophagus
stomach
Small intestines
mouth
Rectum
salivary glands
Large Intestines
Liver