5 Mucosal Membrane

Question 1

Mucosal Membranes
Definition?
Function?
Examples?

Answer 1

The combination of epithelium, basal lamina and lamina propia.
This structure line all moist hollow internal organs of the body.
Most secrete mucus (contains mucins, electrolytes, lysozymes, immunoglobulins)
Functions: stop pahogens and dirt entering body
Prevent bodily tissues from becoming dehydrated
Lubrication

Examples: GI tract, urinary tract, respiratory tract

Question 2

GI tract layers?

Answer 2

Mucosa lining the lumen
Muscularis mucosae
Submucosa
Muscularis externa
Serosa

Question 3

Small vs large intestine

Answer 3

Large have no villi

Question 4

Function of mucosa in GI tract

Answer 4

To absorb substances from the lumen
Prevent ingress of pathogens
Move contents and expel waste

Question 5

Urinary tract structure kidney

Answer 5

Structural unit in the kidney is the nephron
The corpuscle lining is flattened squamous epithelium
Lining of collecting ducts are cuboidal epithelium
Proximal tubes contain ciliated surface
Theres a basal lamina around each tubule

Question 6

Urinary tract structure bladder

Answer 6

In to out:
Lumen, epithelium (transitional), muscularis mucosa, lamina propria, inner longitudinal muscle, outer circular muscle

Transitional epithelium: urothelium

Question 7

Urinary tract structure Urethra

Answer 7

Similar to bladder except transitional epithelium change to squamous.

Mucus glands produce large amounts of sticky mucus and so prevent ingress of pathogens

Question 8

Respiratory tract function

Answer 8

Gaseous exchange and transport
Conducting portion: nasal cavity to bronchioles
Respiratory portion: bronchioles to alveoli

Question 9

Trachea

Answer 9

Divides two primary bronchi in the mid-thorax. Has cartilage to stop collapse

Question 10

Trachea and primary bronchi structure

Answer 10

Mucosa (covered in cilia) thin lamina propria (rich in immune cells and layer of elastic fibres). Has unusually thick basement membrane
Submucosa
C shaped hyaline cartilage (perichondrium and chrondrogenic)
Theres no outer layer of smooth muscle

Question 11

Secondary and Tertiary Bronchi

Answer 11

Similar to primary except cartilage is no longer present as full rings
Ciliated

Question 12

Alveolus structure

Answer 12

In alveoli the capillaries are lined with flattened specialised epithelial cells that attached to a fused basal lamina with thinner epithelial cells of the air sac on the opposite side.
The folds in the basal lamina allows stretch of air sacs
Collagen present with elastin (connective tissue) to allow elastic recoil when air sacs empty