Thoracic cavity

Question 1

Describe anatomy & innervation of thoracic wall

Answer 1

Walls formed by ribs & intercostal muscles laterally & diaphragm caudally

True ribs: articulate directly with sternum

False ribs: articulate indirectly through connection of cartilage with that in front

External & internal muscles occupy intercostal spaces
Innervated by thoracic spinal nerves

Question 2

Describe anatomy & innervation of diaphragm

Answer 2

Major muscle of inspiration
Motor & sensory innervation by phrenic nerve

Question 3

What are serous membranes

Answer 3

Surface of inner wall of body cavities lined by serous membrane
Single layer of epithelium with thin underlying connective tissue

Membrane named pleura in thoracic cavity
Each lung has serous membrane around it called pleura
Contact region between right & left pleural sac is mediastinum

Question 4

Label the pleura

Answer 4

Question 5

Function of the pleural cavity

Answer 5

Narrow space between parietal & visceral pleura is pleural cavity

Contains serous fluid spread over surface

Establishes adhesion with thoracic wall

Facilitates smooth movement

Question 6

What is the mediastinum & what structures does it contain

Answer 6

Space between left & right pleural sacs

Contains: heart, thymus, portions of oesophagus & trachea, blood vessels & nerves