2.1 Anatomy of the Respiratory System Flashcards
What is the bony thorax made up of?
12 thoracic vertebrae
12 ribs with costal cartilage
Sternum- clavicles, manubrium, body, xiphoid process
What are the 3 intercostal muscles called?
External intercostal muscle
Internal intercostal muscle
Innermost intercostal muscle
Which way do the muscle fibres run in the external intercostal muscle?
Downwards and anteriorly
Which way do the muscle fibres run in the internal and innermost intercostal muscles?
Downwards and posteriorly
What do the intercostal muscles move?
The upper ribs to increase the diameter of the thorax
The lower ribs to increase the lateral diameter.
What runs along the costal groove in the back of the ribs?
Neurovascular bundle
What nerves can be found in the costal groove?
What do they innervate?
Anterior rami of thoracic spinal nerves
Nerve innervate intercostal muscles, parietal pleura and overlying skin
What arteries can be found in the costal groove?
What do they supply?
The posterior and anterior intercostal arteries
Supply the intercostal muscles, parietal pleura and the overlying skin
What is the venous drainage of the intercostal veins?
Drain into Azygos system which leads to the superior vena cava.
What is the diaphragm?
A dome shaped muscle at the base of the thoracic cavity
What happens when the diaphragm contracts?
Moves downwards
Inspiration occurs
What levels are the 3 openings in the diaphragm at?
T8- Vena Cava
T10- Oesophagus
T12 Aortic hiatus
What nerve supplies the diaphragm?
Phrenic nerve
Nerve roots- C3,4,5
How does expiration occur?
Passive process due to elastic recoil of the lungs
How does the pleura aid respiration?
The pleura sticks the lungs to the abdominal wall. When the abdominal cavity expands so do the lungs
