Week 8 Lecture 16 Flashcards
(37 cards)
Upper respiratory system parts
Nasal cavity, Larynx, pharynx,
Lower respiratory system parts
Trachea, bronchioles, alveoli
Pleural Cavity
- occupies space within the thoracic cavity (where we find structures associated with the heart
- two pleural cavitites on each side
- houses lungs and associated structures
What is the pleura
The pleura are two thin layers of tissue that wrap around each lung, like a protective covering.
- fluid filled membrane
- lungs develop into the pleural sac
- it surrounds the lungs during development, those lung buds grow towards the pleural membrane
Parietal pleura
- ## superficial on body wall against the thoracic wall
Visceral pleura
- deep directly on lungs
- continuous on hilum (where the blood vessels and tubes come in and out)
Pleural cavity purpose
- maintain surface tension so our lungs are extanding with each inhalation
- lungs are very elastic and they the tendency to recoil
- the parietal and visceral layer is continuous at the hilum
Pleural cavities vs pleural space
Pleural cavitites are the physical spaces to the right and left of the mediastinum that houses the lungs.
Pleura space fluid filled space before the two layers of pleura.
General features of the lungs:
- Pyramidal (apex more superiorly and then widens out into a base inferiorly)
- Diaphragmatic surface (along the inferior border of both lungs in contact with the respiratory system)
- costal surface (anterior, lateral and posterior surface, all in contact with the ribs)
- Mediastinal surface (in contact with the mediastinum)
Lobes of the lung
- lungs are not symmetrical, left lung only has two lobes
- right lobe has three: superior, middle and inferior
-less space for the left lung because the heart apex is there
What are Fissues
- fissues are lines between each lobe (naturally)
Blue = oblique fissue
Green = horizontal fissue (only on right side)
Specific Features of the Right Lung
- there are grooves on the lungs bc of surrounding structures
- costal grooves all along the lungs
dark blue = esophagus
teal = superior vena cava
Specific Features of the Left Lung:
- costal impression (from the ribs)
- lingula (red) (on the medial and inferior lip)
- you can see the cardiac notch (pink) on the posterior side due to the heart
- the loop on the posterior side is due to the aorta (green)
Hilum
- root of the lung
- ## this is where the parietal pleura is reflecting on itself to become continuous with the visceral pleura
Vessels in the Hilum
- pulmonary arteries (superior), deoxygenated blood
- pulmonary veins (inferior/anterior)
- bronchi (posterior), very cartilaginous, a lot toughter than the rest of the structures
- pleura reflects on itself
Trachelobronchial tree
Nasal cavity –> pharynx –> larnyx –> trachea –> primary bronchi –> secondary bronchi (lobular) –> tertiary bronchi (segmental) –> terminal bronchioles –> respiratory bronchioles –> alevoli
- the ones above is the conducting portion (carry air in and out of the lungs but don’t actually do gas exchange)
- respiratory bronchioles and alevoli are special because of gas exchange
Label these and talk about them
- Trachea (teal): large and has cartilaginous rings. Descending from the larynx and going to bifurcate into two primary bronchi.
- Secondary bronchi (purple) (lobular bronchi): one to each lobe, 5 lobes
- Tertiary bronchioles (go to each segment of the lobes, more than 20)
What are alveoli for?
- air filled sacs (look like grapes), go back to bigger branches backwards
Trachea
- cartilaginous rings: not a complete full circle,
- smooth muscle (posterior), on the back, the cartilage is replaced by smooth muscle
- the digestive system (esophagous is going to be posterior to the trachea. The esophagous needs to have food pass in it so the behind of the trachea can’t be too rigid.
Trachea Bifurcate
- R/L Primary Brochi
- Carina (division site)
- T4 and T5 (start of the aorta)
- Right primary brochi is wider and it has a more vertical slope to it compared to the left one
- if someone were to choke, it is more likely to go to the right lung than the left lung
Gas exchange 3 structures
- structure from the respiratory system interacting with the cardiovascular system
Alveoli: air filled sacs, bunches of grapes. Is where gas exchange occurs and red blood cells become deoxygenated.
Pulmonary arteries: deoxygenated blood away from the heart
Pulmonary veins: oxygenated blood towards the heart
What do alveoli interact with?
- capillary network around them
- close contact with endothelial cells and RBC within vessels
Mechanism of gas exchange:
- gas relies on the ability concentration gradient
- the capilary network has deoxygenated blood
- O2 diffuses from alveolus space into capillary –> bonds to RBC
- O2 on RBC travels through pulmonary vein to heart to systemic circulation
- carbon dioxide passively travels from the deoxygenated blood into the alveolus space
Innervation fo Respiratory System: Sympathetic Innervation
Sympathetic Innervation
- spinal nerves T2-T5
- post synaptic fibers from sympathetic chain where they will synapse
- postsynaptic fibers are going to travel directly to innervate teh trachea and bronchi tissues
- cause the smooth muscle to relax in bronchi
- bronchodilation (increase so we have as much air as possible)
