3. Internal Surfaces of the Body Flashcards
What does the mucous membrane consist of?
Epithelium lining the lumen of the tube and the connective tissue - lamina propria. In the alimentary tract, there is a third layer which consists of smooth muscle cells that is called the muscularis mucosae.
What does the serous membrane line? (Give three examples).
It lines close body cavities, that don’t open to the exterior. E.g. Lining the peritoneum, the pleural sacs and the pericardial sac.
What does the serous membrane consist of?
Simple squamous epithelium which secretes watery lubricating fluid and a thin layer of connective tissue that attaches the epithelium to adjacent tissue.
What are the four layers of the gut? (From the innermost to the outermost).
The mucosa, submucosa, external muscle layers, serosa.
What does the mucosa of the gut wall consist of?
The muscularis mucosae, lamina propria and epithelium.
What are the two layers of the muscularis externa of the gut wall?
The outer longitudinal layer and the inner circular layer.
What is the purpose of the muscularis externa of the gut wall?
To create successive peristaltic waves to move food along the gut.
What type of epithelium is in the oesophageal mucosa?
Stratified squamous non-keratinised.
In the respiratory tract, where does the conducting portion go from and to?
From the nasal cavity to the bronchioles.
In the respiratory tract, where does the respiratory portion go from and to?
From the respiratory bronchioles to alveoli.
What is the predominant epithelium found in the alveoli and why? What is the other type of epithelium and what is its role?
90% of the cells are squamous to allow effective gas exchange. The other 10% are cuboidal cells and keep the alveoli open by producing surfactant.
Why are transitional epithelium found in the bladder, ureter and urethra?
To allow them to expand and contract.
What are the respective lengths of male and female urethras and what is the effect of this on ease of catheterisation?
20cm and 3-4cm so it is easier to catheterise females as there is less far to travel with the needle.
What does the mucous membrane line? (Give three examples).
It lines internal tubes which open to the exterior. E.g. The alimentary tract, respiratory tract and urinary tract.
