Internal Surfaces Of The Body

Question 1

Serous Membranes

- line closed body cavities and envelope the viscera (organs)

Answer 1

• simple squamous epithelium (mesothelium) which secretes a watery lubricating fluid which promotes a relatively friction-free movement of the structures they surround
• thin layer of connective tissue which attaches the epithelium to adjacent tissue (also carries blood vessels and nerves)
  PERITONEUM
  PLEURAL SACS
  PERICARDIAL SAC
  During embryonic develop,Meg the heart, lungs and gut develop next to a be-like cavity in which the invaginate - become surrounded by serous membrane

Question 2

The gut wall

Answer 2

THE MUCOSA (innermost)
- epithelium
- lamina propria
- muscularis mucosae
THE SUBMUCOSA (connective tissue - has glands, arteries, veins and nerves)
MUSCULARIS EXTERNAE (creates successive peristaltic waves to move luminal contents along the gut)
- inner circular layer
- outer longitudinal layer
THE SEROSA (outermost - a serous membrane)

Question 3

Oesophagus

Answer 3

Convoluted lumen that can expand
THE MUCOSA
- epithelium (stratified squamous non-keratinised)
- lamina propria (loose connective tissue with blood & lymph vessels)
- muscularis mucosae
THE SUBMUCOSA (connective tissue containing mucus secreting glands)
MUSCULARIS EXTERNA (moves food by peristalsis)
- inner circular layer
- outer longitudinal layer
ADVENTITIA
- thin outermost layer of connective tissue

Question 4

Stomach

has rugae - longitudinal ridges

Answer 4

THE MUCOSA 
- epithelium 
- lamina propria
- muscularis mucosae 
THE SUBMUCOSA 
MUSCULARIS EXTERNA (3 layers) 
- oblique 
- circular
- longitudinal

Question 5

Respiratory Tract

Answer 5

Conducting Portion
= nasal cavity to bronchioles
Respiratory Portion
= respiratory bronchioles to alveoli

Question 6

Trachea

Answer 6

The C-shaped cartilaginous tracheal ring can be transformed partially to bone - process that concurs with ageing
The fibroblast if membrane contains the trachealis muscle

Question 7

Alveoli

Answer 7

Type I - squamous - 90% of SA - thin for gas exchange with capillaries (across blood-air barrier)
Type II - cuboidal - 10% of SA - produces surfactant
Many macrophages line alveolar surface to phagocytose particles (microbes and dust)

Question 8

The Ureter

male ~ 8 inches, female ~ 1.5 inches

Answer 8

• transitional epithelium
• fibroelastic lamina propria
• circular muscularis externa

Question 9

Bladder wall

Answer 9

• transitional epithelium
• smooth muscle
• muscularis externa (3 interwoven layers)

Question 10

Mucous membranes

- line certain tubes which open to the exterior

Answer 10

• and epithelium lining the lumen of a tube
• an adjacent layer of connective tissue (lamina propria)
• alimentary tract has a third layer - smooth muscle (muscularis mucosae)
  ALIMENTARY TRACT
  RESPIRATORY TRACT
  URINARY TRACT