8: Histology Flashcards
What kind of epithelium is found in the oral cavity, oropharynx and laryngopharynx?
Stratified squamous epithelium
Which kind of epithelium is found in the nasal cavity and nasopharynx?
Ciliated, pseudostratified, columnar epithelium with goblet cells
i.e respiratory epithelium
What is the ventral surface of the tongue?
Underside of the tongue
What is the dorsal surface of the tongue?
Top
Name the four kinds of papillae found on the tongue.
Fungiform
Circumvallate
Filiform
Foliate
Which papillae aren’t tastebuds and instead aid in the manipulation of food around the mouth?
Filiform papillae
What is found in the submucosa of the oesophageal lining?
Submucosal glands
In which two parts of the GI tract are glands submucosal?
Oesophagus
Duodenum
What is the gastro-oesophageal junction also known as?
Z line
What is the epithelial transition at the gastro-oesophageal junction / Z line?
Stratified squamous epithelium
to
Columnar epithelium
What is found in the mucosa of stomach cells?
Gastric pits
which contain gastric glands
What are found in the gastric pits of stomach cells?
Gastric glands
Give two examples of cells found in the gastric pits?
Parietal cells
Chief cells
What do parietal cells secrete?
Intrinsic factor (for Vitamin B12)
Hydrochloric acid
What do Chief cells secrete?
Pepsinogen (precursor of pepsin, a digestive enzyme)
What is unusual about the muscularis externa of stomach cells?
It has an additional layer of muscle
probably for mixing and churning food
At the ___ ___, the smooth muscle thickness of the muscularis externa increases.
pyloric sphincter
What are the finger-like projections found on the mucosa of small intestinal surfaces?
Villi
What is the proper name for the pits found next to villi on the small intestinal mucosa?
Crypts of Lieberkuhn
What are enterocytes?
Main absorptive cells of the small intestine
tall, columnar and with brush borders
What are goblet cells?
What do they produce?
What does this substance do?
Small intestinal glands
Mucin
Protects and lubricates cells; move things along
Where are paneth cells found?
What is their function?
Bottom of Crypts of Lieberkuhn
Antibacterial
What cells produce hormones to control gastric secretion and motility?
Enteroendocrine cells
Give two examples of hormones secreted by enteroendocrine cells.
CCK, VIP, Gastrin
What cells, found in the Crypts of Lieberkuhn, divide to replenish the epithelium?
Stem cells
Where in the small intestine are Brunner’s glands found?
Duodenum
What is the function of Brunner’s glands?
Release alkaline mucous (bicarbonate?) to neutralise HCl in chyme
remember that bile is alkaline
Where in the small intestine are the tallest villi found?
Jejunum
Which folds, found in the jejunum, allow the villi to be tall and prominent?
Plicae circularis
big folds
What lymphoid tissue is found in the ileum?
Peyer’s patches
In the large intestine only, the longitudinal muscle of the muscularis externa is split into three layers - what are these layers called?
Teniae coli
so:
Mucosa (epithelium, lamina propria, muscularis mucosae)
Submucosa (w/ glands sometimes)
Muscularis externa (circular, longitudinal (teniae coli))
Serosa
The teniae coli are found in the (circular / longitudinal) muscle layer of (small intestine / large intestine).
longitudinal
large intestine
Which offshoot of the caecum has a lot of lymphoid tissue?
Appendix
___ tissue in the appendix declines with ___.
Lymphoid
age
Which nervous system is found within the digestive tract?
Enteric nervous system
What are the two nerve plexuses visible in GI tract tissue?
Submucosal plexus (in the submucosa)
Myenteric plexus (between the circular and longitudinal muscle of muscularis externa)
In which layer is the myenteric plexus visible?
Muscularis externa
In which layer is the submucosal plexus visible?
Submucosa
oxyntic cells are “pink fried eggs with purple yolks” slide 19
large intestinal crypts “like test tubes in a rack”
