Lecture 16 Flashcards
What does the thoracic cavity contain?
- Mediastinum
- Pleural cavities
- Boundaries
Mediastinum
Heart, vessels, and pericardium
Pleura cavities
Lungs are separate so if one-stops functioning you have another
Pressure
Is inversely proportional to volume. If volume goes up, the pressure goes down.
Does the volume increase or decrease when we breathe in?
Increase
The equation for Boyle’s law
P=1/V
What is pressure measured by?
Collisions. Smaller space = more collisions = increased pressure
What type of joints are sternocostal
Synovial except the first which is cartilaginous
What type of joints are costochondral
Cartilaginous
What type of joints are Interchondral
Synovial
Where is the costotransverse joint located?
Between the rib and transverse process of vertebrae
Where is the costovertebral located?
Between the rib and body of the vertebrae
What is the diving reflex triggered by?
The cooling and wetting of the face and nose. It sends more O2 to the heart and brain and increases time holding your breath
What happens to the diaphragm when it is contracted?
Flattens
Intercoastal muscles
Attach diagonally between neighboring ribs.
External intercostals
Lift ribcage and expand cavity.
Internal intercostals
Depress ribcage and decrease cavity. Expiration - Forced breathing.
Accessory muscles
Several muscles attach to the thoracic cage.
During quiet breathing what happens to the diaphragm and external intercostal muscles?
Diaphragm contracts (flattens) and the external intercoastal contract (lift ribs)
During active forced inspirations
Accessory muscles contract to further expand the thoracic cavity
During active ‘forced’ expirations
Internal intercoastal muscles contract and depress ribs. Accessory muscles contract to decrease cavity volume.
What helps the lungs to ‘stick’ to the wall?
The pleura
Do lungs decrease/increase during expiration
Decrease
What type of pleura is on the thoracic wall?
Parietal pleura
What type of pleura is on the lungs?
Visceral pleura
What type of pneumocytes form the alveolar wall?
Type 1 pneumocytes
What shape is the diaphragm when it’s relaxed?
Dome-shaped
What type of muscle is the diaphragm made of?
Skeletal muscle
What does the diaphragm separate?
The thorax from the abdomen
Olfaction is
Specialised epithelia
External intercostal muscles are involved with
inspiration
Internal intercostals are involved in
Forced expiration
Accessory muscles assist with
Forced inspiration or expiration
During forced expiration the diaphragm ______ and the _____costals ______
Domes, internal, contract
