Flashcards in Internal surfaces Deck (43)
What are the layers of a mucous membrane?
-Epithelium lining the lumen
What is the lamina propria?
-Thin layer of connective tissue
What is muscularis mucosa?
-Smooth muscle in mucous membranes
What structures do mucous membranes line?
-I.e. internal tubes which open to the exterior
What are serous membranes?
-Two part membranes which line closed body cavities which envelope viscera
-I.e. peritoneum, pericardium, pleural sacs
What is the function of serous membranes?
-Secrete lubricating fluid promoting friction-free movement of the viscera they surround
What type of epithelium are serous membranes?
-Simple squamous epithelium (mesothelium)
-How to serosae come to surround viscera?
-The viscera invaginate into the serosae becomming surrounded.
-The membrane closest to the organ is the visceral membrane
-The opposing membrane is the periatal membrane
What makes up the alimentary canal?
-Duodenum, jejenum, ileum
What are the layers of the alimentary tract wall?
What is the mucosa made up of?
What is the immune adaption of the mucosa of the ileum?
-Peyers patches (aggregations of lymphocytes) in the lamina propria
What is the adaption of the mucosa in the stomach?
-Rugae (folds of gastric mucosa)
What is an adaption of the jejenum?
-Pilcae circulares (folds of mucosa/submucosa into lumen) which have villi which have microvilli
-Greatly increase surface area
What is an adaption of the colon mucosa?
-Have crypts of lieberkuhn which secrete mucus
What is submucosa?
-Connective tissue which lies underneath the mucosa
-Contains glands, blood vessels and nerves
What is the muscularis externa?
-Smooth muscle which surrounds submucosa
-Has two layers - inner circular layer and outer longitudial layer
-surrounded by serosae
What is the function of the muscularis externa in the alimentary canal?
-Peristaltic waves to move lumen contents along
What is adventitia and when is it present?
-Thin layer of connective tissue
-Present when there is no invagination of viscera into the pericardium, pleural sac or peritoneum
List the conducting portion and the respiratory portions of the respiratory tract?
-Conducting portion - nasal canal, nasopharynx, oropharynx, larynx and trachea
-Respiratory portion - bronchi, bronchioles, lung, alveolar ducts, alveoli and diaphragm
What is the epithelium of the respiratory tract?
-Pseudostratified, ciliated epithelia
What is the epithelium of the oesophagus?
-Stratified squamous non-keratinised
What is the epithelium of the majority of the alimentary tract?
What are the cell types in the alveoli?
-Type 1 squamous (90%)
-Type 2 cuboidal which secrete surfactant
What are alveoli surrounded by?
-A basketwork of capillaries and elastic fibres
What immune cell type lines the alveoli?
List the layers of the respiratory tract walls
Which section of the respiratory tract has adventitia?
What type of glands are in the submucosa of the trachea?
What unicellular glands are present in the respiratory tract and upto what point?
-Upto bronchioles as the lumen gets narrow, mucus would block it.
What is the function of the trachealis muscle and where is it located?
-At the back of the trachea, anterior to the oesophagus
-Can open and close the trachea to an extent
Describe the hyaline cartilage of the trachea and state its purpose
-C shaped rings
-to keep the airways open
-Upto what point in the respiratory tract is cartilage found?
-Down to the bronchioles
-What keeps the bronchioles open?
-The surrounding alveoli
What happens to the hyaline cartilage of the respiratory tract with age?
-Partly transforms to bone
What makes up the urinary tract?
-Kidney, ureter, bladder, urethra
What epithelium is present in the bladder, ureter and urethra and what is its function?
-Distensibility and protection from toxic chemicals
What are the layers of the mucosa of the bladder?
-no muscularis mucosae
Why is the bladder impermeable to urine?
-Intracellular tight junctions
What adaption does the muscularis externa of the bladder have?
-Has three layers instead of two
Does the bladder, ureter and urethra have adventitia or serosa?
Why are females more prone to urinary tract infections
-Female urethra 1.5 inches
-Male urethra 8 inches