GASTROINTESTINAL Flashcards
What is the alimentary canal?
Also called the GI tract- mouth to anus- plus accessory organs (teeth, tongue, salivary glands, liver, gallbladder, pancreas)
What are the walls of the GI tract?
Mucosa
Sub mucosa
Muscular is
Serous/adventita
What is mucosa?
Inner layer- has 3 distinct layers
Epithelium- epithelial cells- rapid renewal, comes into contact with digested food
Lamina propria- many blood vessels and lymph tissues MALT lives here
Muscularis mucosa- smooth muscle fibers, has many folds for better absorption especially in stomach and small intestines
What is submucosa?
Binds muscles to muscularis layers, many blood vessels and lymphatic vessels and a neural plexus called the sub mucosal plexus
What is the muscularis layer?
Muscle layers
Skeletal muscle (voluntary) in mouth, pharynx, esophagus and external sphincters
Smooth muscle ( involuntary) everywhere else, contains the Myentaric neural plexus, these muscles contract and relax to help break down food and mix it with secretions and propel it forward
Inner sheet of circular fibers
Outer sheet- of longitudinal fibers
What is the serous a/adventitia layer do?
Outermost layer
A serous membrane
Attaches organs to surrounding tissues in the abdominal cavity
Not found in esophagus
This layer is also called the visceral peritoneum
What does the salivary glands do-
Produce saliva or salivary amylase (breaks down carbs)
Begin the chemical breakdown of food
Controlled by parasympathetic of ANS
Where is the parotid gland?
In cheek
Where is submandibular?
Floor of mouth
Where is sublingual
Beneath the tongue
What kind of muscles does the tongue have?
Skeletal muscles covered by a mucus membrane
What are the tongues extrinsic muscles?
Originate outside the tongue, move food around to form a blus
Hat do the intrinsic muscles of the tongue do?
Originate inside the tongue, and changes shape
What does the surface of the surface of the tongue do/have?
Covered with papillae with taste buds
What does the lingual glands do?
Secrete mucus, lingual lipase (triglyceride digestion)
What does teeth do in digestion?
In sockets in mandible and maxilla bones held in by periodontal ligaments
What is the pharynx composed of and what does it contain?
Skeletal tissue and lined with mucus membranes
Nasophaynx
Orophayrnx
Larynfopharynx
Peritoneum- what is it and what are the 2 layers called?
Wraps around the abdonminopelvic organs
The largest serous membrane in the body
Made of large folds that bind organs together and bind them to the abdominal walls
2 layers filled with a lubricating serous fluid called
Parietal peritoneum- lines the walls of the abdominal cavity
Visceral- covers the alimentary canal and some organs in the abdominal cavity
The largest folds of the peritoneum have names- what are they?
Greater omentum
Lesser omentum
Mesentary
Mesocolon
Falciform ligament
What is the greater omentum
Largest peritoneum fold
Called the “fatty apron”
Drapes over the transverse colon and small intestines
Many blood vessels
Lymph nodes
Lymph nodes
Adipose tissue like a “beer belly”
What is in the retroperitoneal space?
Kidney and ureters
Most of the pancrease
Adrenal glands
Aorta (abdominal)
Inferior vena cava
Esophagus-what is its role?
Secretes mucus and transport food to stomach by peristalsis
What does the superior/upper 1/3?
Skeletal muscle (upper sphincter lives here)
Hat does the middle 1/3 esophagus consist of?
Both
Skeletal muscle
And
Smooth muscles
