Ch 23: Digestive System Flashcards
It’s purpose is to break down or digest the food into particles smaller and simpler enough to be absorbed by your body’s cells.
Digestive system
It’s purpose is composed of four functions: ingestion, digestion, absorption and desiccation
It is a hollow muscular tube extending from mouth to anus consisting of: mouth, for Alex, esophagus, stomach, small intestine, and large intestine, rectum, and anus
Accessory organs include: Salivary gland’s, teeth, liver, gallbladder, pancreas and tongue
Alimentary canal or G.I. tract
This involves the breaking down of food
Two types:
- mechanical: breakdown of large food particles into smaller particles by physical means
- chemical: Alteration of food by chemical means involves digestive enzymes from the mouth, stomach, and testing, acid and bile
Digestion
This is the movement of the end products of digestion movie across the walls of the digestive tract into the blood for distribution throughout the body, what’s not digested ends up as a waste
Absorption
This is formed by four layers:
- mucosa
- submucosa
- muscle layer
- Serosa
Layers of the digestive track
A layer of the digestive track
Innermost layer of mucous membrane
mucosa
A layer of the digestive track
Lies next to the mucosa, Blood vessels, nerves and glands
submucosa
A layer of the digestive track
Two layers; enter circular and outer longitudinal
Responsible for contraction and relaxation mixes food mechanically
Involves peristalsis
Muscle layer
Pushes food from one part of the G.I. tract to another
Stimulated by the presence of food
Peristalsis
A layer of the digestive track
Outer most layer that extends to the peritoneum
Attaches digestive organs to wall cavity
Seriously what
External Nervous system regulates the gut movement and secretions
Part of the Parasympathetic nervous system (rest and digest)
Innervation
Extensions of the Sabrosa that produce large faults in the abdominal cavity which service several purposes:
- anchors digestive organs
- carries blood vessels, length vessels and nerves to the abdominal organs
- mesentery and mesocolon are located behind the digestive organs
- greater and lesser omentum’s are located behind the digestive organs
Peritoneal membranes
A structure or organ of the digestive track
Includes:
- teeth
- tongue
- salivary gland‘s
- hard and soft palate
- uvula
Mouth
A structure or organ of the mouth
Choose food into smaller pieces by mastication
Two sets: 20 deciduous and 32 permanent:
- Incisors
- canines /cuspids
- premolars bicuspids
- molars (includes 4 wisdom)
Teeth
A structure or organ of the mouth
A muscular organ that facilitates chewing and swallowing by forming a bolus
Allows for test (sweet, sour, salty and bitter)
Frenulum Anchors it to the floor of the mouth
Tongue
A structure or organ of the mouth
Includes three pairs:
- parotid gland
- Submandibular glands
- Sublingual glands
1 L of saliva is produced daily to moisten and soften foods
salivary gland’s
A structure or organ of the mouth
Forms the roof of the mouth
Two types:
- anterior hard: separates oral cavity from nasal passages
- posterior soft: separates the oral cavity from nasopharynx
Hard and soft pallets
A structure or organ of the mouth
Part of the soft palate that extends towards the back of oral cavity; plays a role in swallowing
Uvula
A structure or organ of the digestive track
Comprised of three parts:
- nasopharynx (not part of the digestive system)
- Oropharynx
- laryngopharynx (includes epiglottis: gatekeeper 1)
Pharynx or throat
A structure or organ of the digestive track
The food tube that carries food from the Pharynx to the stomach
Two types of sphincters:
- pharyngoesophageal
- Lower esophageal sphincter
Esophagus
A Sphincter of the esophagus
Located at the top of the esophagus
Gate keeper number two
pharyngoesophageal Sphincter
A Sphincter of the esophagus
Gatekeeper number three
Involved in Gastro esophageal reflux disease by causing a burning sensation
Lower esophageal sphincter
This organ of the digestive track does the following actions::
- secretes gastric juices, enzymes and hormones
- regulates movement of food into the duodenum
- Digest carbohydrates and proteins
- absorbs small amounts of water, certain drugs and alcohol
Different regions include:
- fundus: Top
- body
- pylorus: Bottom (includes gatekeeper # 4)
- greater and lesser curvature
- regae: Thick folds that allow 4 expansion when empty
Stomach
