Internal Surfaces Of The Body Flashcards
What are the three layers of a mucous membrane?
Epithelium Lamina propria (connective tissue) Muscularis mucosa (in the alimentary tract)
Which tubes are lined by mucous membranes?
Alimentary canal
Respiratory tract
Urinary tract
Where are serous membranes found?
Pericardium, pleural sac, peritoneum.
What are the functions of a serous membrane?
Secrete lubricating fluid
Attach the epithelium to adjacent tissues.
Carry blood vessels and nerves.
What are the two layers of a serous membrane?
Mesothelium
Connective tissue
How do the organs and their associated serosa develop embryologically?
Develop next to cavity, then invaginate.
Where are the parietal and visceral serosa?
Parietal is the outside of the serosa, visceral is adjacent to the organs.
What is the mesentery?
Part of the peritoneum that attaches the organs to the abdominal wall, supplied with blood and lymph vessels.
What are the four layers of the gut wall?
Mucosa, submucosa, muscularis externa, serosa
What are the three layers of the mucosa?
Epithelia, lamina propria, muscularis mucosa
What is often present in the lamina propria?
Peyers patches (aggregations of lymphocytes) and mucosal glands.
What is found in the submucosa?
Glands, arteries, veins, nerves.
What are the two layers of the muscularis externa?
Inner circular layer
Outer longitudinal layer
(Both actually spirals)
What sort of connective tissue is found in the lamina propria?
Loose.
What is found in the lamina propria of the oesophagus?
Many cells of the immune system.
Blood vessels and nerves.
Smooth muscle cells
What connective tissue surrounds the oesophagus?
Adventitia (not peritoneum)
What is secreted by the gastric mucosa?
Acid, digestive enzymes, gastrin (hormone)
How many layers does the muscularis mucosa of the stomach have, what are they?
Innermost oblique layer - responsible for creating motion that churns food.
Middle circular layer
Outer longitudinal layer
What are rugae?
Folds in gastric mucosa that cause longitudinal ridges in empty stomach.
What are plicae circulares?
Circular folds of mucosa and submucosa that project into gut lumen.
What is the conducting portion of the respiratory tract?
Nasal cavity to bronchioles
What is the respiratory portion of the respiratory tract?
Respiratory bronchioles to alveoli
What are the layers of the tracheal wall?
Mucosa: pseudostratified ciliated columnar epithelium, lamina propria
Submucosa
Hyaline cartilage
Adventitia
What cells are found in the bronchioles and further down the respiratory surfactant, and what is their function?
Club cells -secrete surfactant.
What cells are present in the alveoli, in what proportion, and what is their function?
90% of the surface area is squamous cells (type 1) which permit gaseous exchange.
10% of the surface area is cuboidal cells (type 2) which secrete surfactant
There are numerous macrophages.
What are the three layers of the ureter?
Transitional epithelium
Fibroelastic lamina propria
Circular muscularis externa
What features of the transitional epithelium confer impermeability to urine?
Thick plasma membrane, intercellular tight junctions.
What is the change of shape of the urethra during urination?
Stellate to ovoid.
What are the layers of the wall of the bladder?
Transitional epithelium
Lamina propria containing smooth muscle.
Muscularis externa - 3 interwoven layers.
What is the length of the urethra in males, and in females?
20cm, and 3-4cm.
