Anat And Cells Flashcards
What are the layers of the gut tube ?
Mucosa
Submucosa
Muscularis externa
Serosa
What is the role of the epithelial layer ?
Absorption, hormones secretion,mucus production,transport and barrier
What is the main role of the lamina Propria ?
Lymphoid
Macrophages
IgA production
What is the function of the muscularis mucosa ?
Keeps epithelium in contact with Submucosa
Helps crypt dynamic
What is found in the Submucosa ?
dense CT
Blood vessels
lymphoid tissue
Plexus
What is the type of epithelium present in the gut ?
Stratified squamous in oesophagus and distal anus
Simple columnar everywhere else
What is an enterocyte ?
Simple columnar cel of the gut tube that absorbs
What is the main specialisation characteristic of the enterocyte ?
Has Microvilli
Described as brush border
How is mucus produced and what is its function in the gut (intestines+colon)?
By Goblet cells
Protects against : friction , acidic environment , bacterial invasion
Which cell produces mucus in the stomach ?
Surface mucous cells aka Foveolar cells
Which features of the gut increases the surface area ? Where are they found ?
Microvilli Villi (small intestines ) Permanent folds (Plicae circulares) Crypts (of Lieberkuhn in intestines and colon) Temporary folds of the stomach (Rugae)
Which cells are found in crypts ?
Stem cells
Paneth cells
Enteroendocrine cells
What is the function of the stem cells in crypts ?
Renew the cells of epithelium every 2-4 days
Basophilic in H&E due to mitosis
What is the function of the paneth cells of the crypts ?
Secrete antibacterial protein to protect stem cells
Eosinophils due to secretory Vesicle
What is the function of the enteroendocrine cells in crypts ?
Secrete hormones to control gut function
Give eg of glandular tissue in the gut (exocrine)
Salivary glands Pancreas Brunners glands (duodenum, mucus HCO3)
What are the layers of the abdominal wall from superficial to deep ?
Skin Fascia/Fat External oblique Internal oblique Transverse abdominis Rectus abdominis Transversalis fascia Peritoneum
Which muscles of the abdominal wall have aponeurosis ?
External oblique
Internal oblique
Transverse abdominis
What is the rectus sheath ?
Aponeurosis of the lateral muscles surrounding the rectus abdominis
Explain the changes in the rectus sheath in relation to the arcuate line
Arcuate line : halfway between pubic symphysis and umbilicus
Above : rectus sheath goes anterior and posterior to Rectus abdominis
Below : only anterior , rectus abdominis rests on transversalis fascia
What is the arcuate line ?
Lower limit of the posterior layer of rectus sheath
Where inferior epigastric vessel pierce rectus abdominis
What is the mesentery ?
Double fold peritoneum attaching viscera to posterior abdominal wall
Which part of the G tract have a mesentery ?
Jejunum Ileum Appendix Transverse colon Sigmoid colon Rectum
What goes through a mesentery ?
Blood vessels, lymphatic system,nerves, fat
What is a peritoneal ligament ?
Double fold of peritoneum connecting two viscera
Or double fold of peritoneum connecting viscera to abdominal wall
What are the two main peritoneal ligament connecting viscera together ?
Gastrocolic
Gastrosplenic
What are the main peritoneal ligaments connecting viscera to abdominal wall ?
Falciform ligament (liver to anterior wall) Triangular ligaments (liver to diaphragm )
What is the function of a sphincter in the GI tract ?
Divide tube in sections
Control movement
Prevent reflux
Name the sphincters of the GI tract
Upper oesophageal Lower oesophageal Pyloric sphincter Sphincter of Oddi Ileo-caecal Internal anal External anal
