Gastrointestinal Function Flashcards
What are 7 general functions of the GI tract?
- Ingestion of food
- Propulsion of food
- Secretion of mucus, water and enzymes
- Mechanical digestion of food
- Chemical digestion of food
- Absorption of digested food
- Elimination of waste products
The ____ is the innermost layer of the gastrointestinal wall and is exposed to dietary nutrients
Mucosa
In the villus, there is absorption of ___ and ___
Water and nutrients
The ____ is the next innermost layer of the GI wall; this carries the nerve plexus that innervates the mucosa and the muscle layers of the intestine
Submucosa
The ____ is the next layer of the GI wall; it contains the circular smooth muscle layer and the longitudinal muscle layer; this layer contacts to drive peristalsis to keep food moving through
Muscularis
The ____ is the outmost layer of the GI wall; it is the secretory adventitial layer; it keeps everything in place and is continuous from the mouth to the anus; it also secretes lubrication
Serosa
The autonomic nervous system controls what in the GI system?
-Direct neural stimulation
-Hormonal
-Peristalsis
-Defecation
Defecation is controlled by internal and external ____ ____
Anal sphincters
The ___ ___ ___ is a set of nerves connected to the autonomic nervous system and it is also connected to the gut; it is the third arm of the ANS (along with sympathetic and parasympathetic)
Enteric nervous system
The enteric nervous system can function ____ of the ANS and interacts with all arms of the ANS
Independently
What influence does the enteric nervous system have on GI function?
Regulates peristaltic reflex, hormones, and secretions
Stress or high fat/sugar intake triggers a response from ____ ___ that leads to increased food intake, increase fat uptake, decreased energy utilization, and decreased anxiety
Neuropeptide Y
Neuropeptide Y also blocks ____ to the CNS which releases pain
Nociceptors
Neuropeptide Y is an ____ chemical
Endogenous
What are some other examples of endocrine hormones that have an impact on the GI system?
-Gastrin
-Ghrelin
-Secretin
-Somatostatin
What are functions of the mouth?
-Mastication (physical breakdown of food in the mouth)
-In the mouth, saliva mixes with the food, and salivary amylase begins to break down carbohydrates and lingual lipases begin to break down fats
-Saliva also lubricates food to travel to the esophagus
The ____ is a passageway to the stomach; food is not being processed or absorbed here
Esophagus
____ is a neural dysfunction resulting in decreased smooth muscle movement in the middle and lower portion of the esophagus
Achalasia
What are the three sections of the stomach?
-Fundus
-Body
-Antrum
The antrum leads to the ____
Pylorus
A lot of food ____ happens in the stomach
Breakdown
The stomach rolls food around to produce ____
Chyme
In the stomach, cells secrete substances to breakdown food and protect against ____
Bacteria
What type of cells secrete gastrin?
G cells