The GI tract Flashcards
What are organs grouped into?
alimentary canal and accessory organs
Alimentary canal
a tube from lips to anus
What are the segments of the canal?
Mouth, Pharynx, Oesophagus, Stomach, Small intestine, large intestine
What are the three body cavities?
Thoracic cavity, Abdominal/ Pelvic cavity, and the body wall enclosing the cavities
What is the Thoracic cavity lined with?
lined with endothoracic fascia
Abdominal and pelvic cavity
lined with transversalis fascia
Fascia
A thin layer of connective tissue that surrounds and holds organs
What is the body wall composed of?
skin, double layer of fascia, muscles and inner fascia
What is the serous membrane?
lines the abdominal cavity, made up of a layer of simple squamous epithelial cells supported by a layer of connective tissue layer that attaches to an underlying structure
What are the 3 different types of serous membrane
Parietal serosa, Visceral serosa and Connecting serosa
Parietal serosa
lines the wall of the cavity
Visceral serosa
lines the organs
Connecting serosa
makes serous fluid (peritoneal fluid), functions to stop adhesions among organs
Peritoneum
thin serous membrane, it lines the abdominal and pelvic cavities
Connecting peritoneum
connects the visceral and parietal peritoneum
Parietal and visceral peritoneum
continuous with each other and connecting peritoneum
Peritoneal pouches
excavations of peritoneum into the pelvic cavity
Peritoneal cavity in males and females
In males it is a completely closed sac, in females it has two small openings (uterine tubes)
What are the walls of the peritoneal cavity separated by?
thin films of serous fluid, it is only potential space
Mesentery Connecting Peritoneum
between intestinal and the abdominal wall
Ligament connecting peritoneum
between visceral and parietal peritoneum
Fold connecting peritoneum
between two visceral peritoneum
Omentum connecting peritoneum
between the stomach and abdominal organs/ abdominal wall
What are the common layers of the alimentary tract?
Tunica mucosa, Tunica submucosa, Tunica muscularis and Tunica serosa
Tunica mucosa
next to the lumen and protected by a layer of mucus
Tunica submucosa
Dense connective tissue that may have glands, Meissner’s plexus
Tunica muscularis
Smooth or skeletal muscle, auerbachs plexus
Tunica serosa
Loose connective tissue
What is the Tunica mucosa split into?
Laminae epithelialis mucosa, Lamina Propria, Lamina muscularis mucosae
Laminae epithelialis mucosa
Surface epithelium , rests on a basal membrane
Lamina propria
Layer of connective tissue, e.g mucosal glands, blood vessels and lymphoid structures
Lamina muscularis mucosae
not always present, thin layers of smooth muscle
Tunica adventitia
serosa if organ is surrounded by other tissues
Tunica serosa
serosa if organ is suspended in body cavity
Mesothelium
what covers simple squamous epithelium in the serosa
Tunica muscularis in ruminants and dogs
entirely skeletal
Tunica muscularis in Humans and Chicken
entirely smooth muscle
Tunica muscularis in Horses and Cats
distal third is smooth, the rest is skeletal
What are the 3 parts of the oesophagus?
Cervical thoracic and abdominal
what does the oesophagus penetrate through?
penetrates the diaphragm through the oesophageal hiatus
