DIGESTIVE SYSTEM Flashcards
T or F
The gastrointestinal (GI) tract or alimentary canal is a continuous tube that extends from the throat to the anus through the thoracic and abdominopelvic cavities
FLASE
The gastrointestinal (GI) tract or alimentary canal is a continuous tube that extends from the mouth to the anus through the thoracic and abdominopelvic cavities
Organs of the GI tract
Mouth,
pharynx,
esophagus,
stomach,
small intestine, and
large intestine
Accessory organs of the GI tract
Teeth,
tongue,
salivary glands,
liver,
gallbladder, and
pancreas
what is Ingestion?
o taking food and liquid into the mouth
Release of substances, water, acid, buffers, and enzymes into the lumen (interior space) of the GI tract
Secretion
T or F
In normal secretion,
- 3-7L of secretions
- Mixing and propulsion: propulsive or peristaltic movement along the GI tract
- Ability to mix and move material along its length is called motility
FALSE
5-7L of secretions
Mixing and propulsion: propulsive or peristaltic movement along the GI tract
Ability to mix and move material along its length is called motility
Mechanical and chemical breakdown or digestion of food
Digestion
Passage of digested products from the GI tract into the blood and lymph
Absorption
Elimination through feces and urine along the GI tract
Defecation
LAYERS OF THE GI TRACT WALL
- Serosa
- Muscularis Externa (or Muscularis)
- Submucosa
- Mucosa
Epithelium - Lamina propria - Muscularis mucosae:
o “Brain of the gut”; special nervous system for the GI tract
Enteric Nervous System
T or F
Sympathetic function: inhibitory effect, which may be caused by anxiety, anger, or fear; has a connection with myenteric and meissner plexus
Parasympathetic function: excitatory effect; has a connection with vagus and pelvic nerves
TRUE
The Enteric Nervous System is composed of how many neurons?
o Consists of about 100 million neurons extending from the esophagus to the anus
What are the CONTROL OF GI TRACT FUNCTION
Neural Regulation?
A. Autonomic Nervous System
B. Enteric Nervous System
What are the Control of the GI tract function Hormonal Regulation
A. GI Tract Hormones
B. Paracrines
Neurocrines
o It is the largest serous membrane of the body
PERITONEUM
The PERITONEUM is divided into 2 parts. What are they?
a) Parietal peritoneum: lines the abdominal cavity wall
b) Visceral peritoneum: cover organs in the cavity
o Largest peritoneal fold, which drapes over the transverse colon and coils of the small intestine like a “fatty apron”
Greater Omentum
Attaches the liver to the anterior abdominal wall and diaphragm
Connects the right and left lobes of the liver (the liver has 4 lobes: right, left, caudate, & quadrate lobes)
Falciform Ligament
Suspends the stomach and duodenum from the liver
Pathway for blood vessels entering the liver and contains the hepatic vein and artery
Binds the jejunum and ileum of the small intestine to the posterior abdominal wall
Lesser Omentum
o Binds the transverse (transverse mesocolon) and sigmoid (sigmoid mesocolon) colon of the large intestine to the posterior abdominal wall
Mesocolon
o Also known as oral or buccal cavity and is formed by the cheeks, hard and soft palates, and tongue
MOUTH
o Composition of saliva:
a. Mucin: makes saliva a good lubricant
b. Lysozyme, IgA: for protection
c. Salivary amylase (ptyalin)
o Function of saliva:
Initial digestion of carbohydrates
Lubrication, swallowing, taste bud stimulation
Protection of the oral cavity
