thorax & breathing Flashcards
where is the thorax?
from the sternum to vertebral column T1-T12
what is the thorax composed of?
rib cage + muscle + sternum
what is contained in the thorax?
heart, lungs, pleura, b.v, nerves
what is the mediastinum?
the central portion of the thorax
which ribs are termed floating?
11 + 12
which ribs are termed false?
8-10
which is the tissue that lines the lungs?
pleura
what type of muscle is the diaphragm?
skeletal but involuntary
where do primary bronchi and b.v enter the lung?
hilum
which lung has 3 lobes and why?
right, left has heart so less space
how are lobes separated in the left lung?
oblique fissures
how are lobes separated in the right lung?
horizontal fissures
what enters/leaves at the hilum?
bronchi, pulmonary vein and artery
what is pleura made of?
mesothelium- fine layer of epithelium
what does parietal pleura line?
whole of thoracic cavity
what does visceral pleura do?
lies against parietal and covers outer surface of lung
what partitions off the mediastinum?
parietal pleura
where is pleural fluid produced?
the space between parietal and visceral layers
which muscles depress ribs?
internal intercostals
which muscles elevate ribs?
external intercostals
which muscle depresses last rib?
quadratus lamborum
what accessory muscles are used in respiration?
sternocleidomastoid, scalene muscles, pectoralis major
what does the sternocleidomastoid do in respiration?
raises the clavicle in forced inspiration
what do scalene muscles do?
raise the first rib in forced inspiration
what does pectoralis major do?
widens the thorax in forced inspiration
what is the blood air barrier composed of?
capillary endothelium-basement membrane, interstitial space, basement membrane of alveolus, alveolar epithelium
