Git Flashcards
What are the 4 basic layers of a tubular organ
Mucosa
Submucosa
Muscularis
Serosa/adventitia
What are the layers of the mucosa
Lamina mucosa
Lamina propria
Lamina muscularis
Describe the lamina propria of tubular organs
Formed by loose connective tissue, contains lymphocytes, plasma cells, mast cells, eosinophils.
Blood and lymph vessels and nerves are present in this layer
Mucosal glands located throughout
Describe the lamina muscularis of a tubular organ
It is a thin layer of smooth muscle located below the mucosa and above the submucosa
What is the propria-submucosa
Layer of connective tissue when muscularis layer is not present
Describe the structure of the submucosa
Made of connective tissue
Contains blood and lymph vessels
Meissners plexus is present (ganglion of fibres of autonomic nerves)
Submucosal glands are at certain sites
Aggregated lymphoid tissue at certain sites
Describe the tunica muscularis
Made up of a inner circular and outer longitudinal layer
Myenteric or Auerbach plexus of autonomic nerves may be present
Describe cells of the tongue
Stratified squamous epithelium that are thick and keratinised dorsally, and thin and non-keratinised ventrally. There are lingual papillae and taste buds present.
What are the types of lingual papillae?
Mechanical; filliform, conicle and lenticular
Sensory (taste buds); fungiform, vallate and foliate
Describe the cellular structure of taste buds
They are clusters of spindle shaped cells open to the surface through taste pores. They may be Chemoreceptors cells Substentacular cells Or basal cells
What cell type is the non-glandular portion of the monogastric stomach
Stratified squamous epithelium, may be keratinised or non keratinised
What cell type is the glandular mucosa region of the monogastric stomach
Simple columnar epithelium (surface mucous cells)
There are gastric glands in the gastric pits that open into the lamina propria region.
Describe the muscularis of the monogastric stomach
Inner oblique layer
Middle circular layer
Outer longitudinal layer
Describe gastric glands of the cardiac region
Formed by simple cuboidal epithelium. And are short, can be simple, branched, coiled and tubular. They secrete mucus (for protection from digestive secretion)
Describe gastric glands of the fundic region
They are simple, branched , straight or tubular.
Cell types include mucous neck cells, Cheif cells, parietal cells, endocrine cells.
What are mucus neck cells and where are they located?
Located in the fundic region of the stomach (in the neck of the gastric pit)
They are a gastric gland, formed of columnar epithelium, with a basal nuclei and a pale (apical) cytoplasm. Their function is unclear
What is the structure and location of Cheif cells, and what is their function?
Cheif cells are cuboidal to pyramidal with a basal nuclei and zymogens in apex. They are located in the fundic region of the stomach.
They function to produce pepsin (zymogens contain Pepsinogen).
Describe the structure, location and function of parietal cells
Look like large Cheif cells, with a granular eosinophilic cytoplasm. They are located in the fundic region of the stomach, and produce hydrochloride acid products.
What do endocrine cells of the fundic region secrete?
Gastrin
Secretin
Cholecystokinin
And other hormones.
What are the layers of the small intestine?
Mucosa
Submucosa
Muscularis
Serosa
What cell type forms the tunica mucosa
Simple columnar epithelium
What are the layers of the tunica mucosa of the small intestine?
Lamina epithelial mucosae (simple columnar epithelium)
Lamina propria
Lamina muscularis mucosae
What is the structure of intestinal glands (crypts of leiberkuhn)
They are simple tubular glands that open at the base of villi
Describe cells of the intestinal villi
Absorbative cells-epithelial cells with microvilli that form a brush boarder.
Goblet cells-dispersed amongst absoptive cells and produce mucinogen.
T lymphocytes may also be present
Describe cells of the intestinal glands
They are epithelial columnar cells. They may be differentiated into absorbative and goblet cells.
Panneth cells present in some species.
Endocrine cells present.
What are paneth cells?
Cells present in ruminants horses rodents and primates
They are pyramidal cells with eosinophillic granular in the cytoplasm they produce peptidase and lysozyme
Describe the tunica mucosa layers of the small intestine
Lamina epithelius Lamina propria ( made of loose vascular connective tissue. Lymphocytes plasma cells mast cells, globule leucocytes may be present. Lacteals are in the lamina propria. Lamina muscularis- smooth muscle, an inner circular and outer longitudinal layer are present, may be very thin and appear incomplete in places.
Describe the function and location of meissners plexus
Autonomic nervous system function. It’s located in the submucosal layer. It is also called the submucosal plexus
Describe the function and location of the myenteric plexus
Functions in autonomic nervous system
Located between the circular and longitudinal muscle layers (muscularis)
It is AKA the Auerbach plexus
What are brunners glands?
Compound tubulo-alveolar glands with ducts that open into bases of intestinal glands. They are located in the duodenum, and there position and secretion varies between species (may be mucus, serous or seromucus)
What are peyers patches
Aggregations of lymphatic nodules
They are gut associated lymphoid tissue, and follicle associated epithelium. They contain M cells.
What is the easiest way to differentiate large and small intestine?
Large intestine has NO VILLI
What are enterocytes
Simple columnar epithelium of the intestines
Describe intestinal crypts and their function
They are burrows between villi. They are lined with epithelium, and are the birthplace of the epithelium that lines the villi. They migrate up to the surface of the villi where they will eventually be sloughed off. They also have an important role in absorbtion as they pump Na Cl and H2O follows
Describe the apical and basement surfaces of intestinal crypt cells
Apical surface contains protein for import of substances into the cell
Basement surface contains protein for export of substances out of cell to the blood stream.
What is the primary function of villi
Absorbtion
What is the primary function of crypts
Secretion
What is the most outer layer of the large intestine
Serosa, until if becomes the rectum, the rectum is adventitia
What is a liver acinus?
A functional unit (not a true physiological structure) of liver that is a Dimond shape formed by two adjacent lobes. Acini are often aggregated as a bunch of grapes. It represents the afferent blood flow to that portion of the liver.
Describe the structure of the liver acinus
Dimond shape formed by two adjacent lobules. It’s divided into zones 1, 2, 3 (central mid and peri acinar zones) zone 1 is where blood first reaches liver cells, so it has the most toxins and molecules for adjustment
Describe the structure of the parotid salivary gland
It is a compound acinar gland-serous secretion
Acini are pyramid-shape cells, surrounded by myoepithelial cells
Secretory cells have basal nuclei and zymogen granules in the apical cytoplasm.
Describe the structure of the mandibular and sublingual salivary glands
They are compound tubulo-acinar glands that secrete seromucus.
Acini cells are secretory and myoepithelial cells surround the acini.
What are the types of ducts, and what are there cellular structures?
Intercalated ducts- made of simple cuboidal epithelium
Striated ducts- within lobules; simple columnar epithelium
Interlobular ducts-stratified columnar epithelium.
What are the functions of the liver?
Synthesis and secretion (glucose, bile acids, albumin, and macromolecules)
Storage (lipid, glycogen, vit A B)
Transformation (oxidisation, hydrolysis, and conjugation of dangerous endogenous and exogenous compounds)
Excretion (bile)
And in neonate haematopoesis
Define paranchyma and stroma
Paranchyma- the functional tissue of an organ
Stroma-the supportive and connective tissue of an organ
Describe a liver lobule
Structural unit of liver in a hexagonal shape. A hepatic Venule (central vein) will be at the centre
The bile duct, portal veins and hepatic arteries form triads on the margins of the lobule and sinusoids form little tracts from the triads to the central vein.
Describe a canaliculus in the liver
It’s essentially a bike canaliculus (bike path) and it’s a thin tube that runs between hepatocytes to collect the bike they secrete
Describe a hepatocyte and their function
Hepatocytes are liver parenchyma cells. Usually have one central nucleus, and an eosinophillic cytoplasm.
They function to modify molecules within the blood (protein synth, carb and lipid metal and detoxification)
What and where is a kuppfer cell
A macrophage cell, packed with dense chromatin, that functions to filter pathogens from blood, as part of the adaptive immune system. They are located along sinusoids of the liver
Describe the organelles of hepatocytes
Many mitochondria
Many Golgi apparatus, rough and smooth Er
Peroxisomes are present
They are a highly metabolically active cell.
What are the components of bile?
Bilirubin bile salts protein and cholesterol
What does the pancreas secrete
Digestive enzymes
Amylase
Lipase
Trypsin
What is the path of pancreatic secretion
Acinar cells to intercalated duct to intralobar duct to interlobular duct to pancreatic ducts.
Describe the structure of the exocrine pancreas
A compound tubulo-acinar glandsurrounded by a thin capsule and interlobar septa.
Acinar cells are pyramidal epithelial cells and Centro acinar cells (at origin of ducts) are cuboidal cells.
Describe the structure of the endocrine pancreas
Pancreatic islets (islets of langerhans) are pale patches amongst the liver. They contain endocrine cells
A cells-glucagon secretion
B cells- insulin producing
D cells-somatostatin secreting.
