Lungs and Mediastinum

Question 1

what is the mediastinum?

Answer 1

central compartment of the thoracic cavity
contains thoracic viscera outside of the lungs
bordered laterally by lungs and pleural cavities

Question 2

what is the mediastinum bordered by anteriorly

Answer 2

sternum

Question 3

what is the mediastinum bordered by inferiorly

Answer 3

diaphragm

Question 4

what is the mediastinum bordered by posteriorly?

Answer 4

thoracic vertebral column

Question 5

what are the two divisions of the mediastinum

Answer 5

superior and inferior

Question 6

what seperates the superior mediastinum from the inferior mediastinum

Answer 6

every around and above the manubrium belongs to the superir mediastinum, everything below the manuberium of the sternum belongs to the inferior mediastinum

Question 7

what viscera belongs to the superior mediastinum?

Answer 7

superior portions of the esophagus and the trachea

Question 8

What vessels belong to the mediastinum?

Answer 8

arch of the aorta and branches, SVC, and bracgiocephalic veins

Question 9

what are the divisions of the inferior mediastinum

Answer 9

anterior mediastinum, middle mediastinum, and the posterior mediastinum

Question 10

where is the anterior mediastinum?

Answer 10

between the sternum and the pericardium (heart)

Question 11

what gland does the anterior mediastinum contain?

Answer 11

thymus gland

Question 12

what does the middle mediastinum contain?

Answer 12

heart and roots and great vessels

Question 13

where is the posterior mediastinum located?

Answer 13

between heart (pericardium) and vertebral column

Question 14

what does the posterior mediastinum contain

Answer 14

thoracic aorta, inferior esophagus, azygous system (axygoys, homozygous, accessory. homozygous)

Question 15

what is the thymus gland

Answer 15

lymphoid organ - important site of white blood cell *T cell) maturation and hormone production

Question 16

where is the thymus gland located?

Answer 16

in the chest, btw lungs and behind sternum

Question 17

what structures make up the conducting portion of the respiratory system?

Answer 17

nasal cavity, pharynx, larynx, trachea, primary brochi, secondary bronchi, tertiary bronchi, bronchioles, terminal bronchioles

Question 18

what does the trachea split into the carina?

Answer 18

the right and left primary bronchus

Question 19

how many lobar/secondary bronchi does the right primary bronchus branch into

Answer 19

3

Question 20

how many lobar/secondary bronchi does the left primary bronchus branch into

Answer 20

2

Question 21

what comes affter the lobar bronchi?

Answer 21

the tertiary/segmetnal bronchi

Question 22

how many tertiary/segmental bronchi are in each lung

Answer 22

9-10

Question 23

what does each tertiary/segmental bronchi supply?

Answer 23

bronchopulmonary tract/bronchioles and terminal bronchioles

Question 24

how many lobes does the right lung have?

Answer 24

3

Question 25

how many lobes does the left lung have?

Answer 25

2

Question 26

what is a distinguishing factor of the left lung?

Answer 26

cardiac notch

Question 27

what does the oblique fissure seperate in the left lung

Answer 27

superior and inferior lobe

Question 28

what does the horixonal fissure seperate in the right lung

Answer 28

the superior and the middle lobe

Question 29

what does the oblque fissure seperate in the right lung?

Answer 29

the middle and the inferior lobe

Question 30

what is the hilium of the lung?

Answer 30

depressed surface at the center of the medial surface of the lung - lies anteriorly to the 5th and 7th thoracic vertebrae, it is the point where various structures (mainly vessels) enter and exit lung

Question 31

in the hilium, which vessel is most superior

Answer 31

pulmonary artery

Question 32

in the lung which structure is most medial

Answer 32

pulmonary vein

Question 33

in the lung which structure is most inferior

Answer 33

pulmonary vein

Question 34

what is the parietal pleura?

Answer 34

pleura that covers the inner surface of the thoracic wall and extends over the diaphragm and mediastinum

Question 35

what is the visceral pleura?

Answer 35

pleura that covers the outer surfaces of the lungs - and extends the fissures between lobes

Question 36

what does the potential space between the visceral and parietal pleura contain?

Answer 36

pleural fluid

Question 37

what does pleural fluid do?

Answer 37

lubricates pleural surface to reduce friction during lung inflation and deflation

Question 38

what does the respiratory portion include?

Answer 38

respiratory bronchioles, alverolar ducts, aveoli + alverolar sacs

Question 39

what is the role of the respiratory portion of the respiratory system

Answer 39

gas exchange

Question 40

what does the alveolar duct end in?

Answer 40

alveolar sac

Question 41

what are alveolar sacs made up of

Answer 41

alveoli

Question 42

what happens at alveoli

Answer 42

main site of gas exchange

Question 43

what gives lungs their spongy appearance

Answer 43

alveoli

Question 44

what makes alveoli so good at gas exchange? (2 things)

Answer 44

1. extensive capilary network surrounds each alveolus 2. elastic fibers surround alveoli which facilitates stretch and recoil during gas exchange

Question 45

what do pulmonary veins do?

Answer 45

carry oxygenated blood to the left atrium

Question 46

what enters and exits via the hilium?

Answer 46

pulmonary arteries and veins (and bronchus)

Question 47

what do bronchial arteries do?

Answer 47

carry oxygenated blood to the lungs and bronchi

Question 48

what do bronchial veins do?

Answer 48

carry deoxygenated blood from lungs and bronchi (blood drains into th azygous system)

Question 49

what does sympathetic innervation do to the airway?

Answer 49

bronchodialation

Question 50

what does parasympathetic innervation do to the airway

Answer 50

bronchoconstriction

Question 51

what does the phrenic nerve do?

Answer 51

innervate the diaphragm

Question 52

how are pressure and volume related in the lungs?

Answer 52

they are inversely related - as lung volume increases, lung pressure decreases so air is drawn into the lungs. as lung volume decreases, pressure in the lungs increases relative to atmospheric pressure - air is drawn out of the lungs

Question 53

what is the primary muscle of inspiration

Answer 53

diaphragm

Question 54

what are the secondary muscles of inspiration

Answer 54

external intercostal muscles (elevate ribs)

Question 55

what are the primary muscles of expiration?

Answer 55

diaphragm

Question 56

what are the secondary muscles of expiration

Answer 56

internal intercostal muscle (depresses ribs)

Question 57

what happens to the alveoli during expiration

Answer 57

elastic recoil

Question 58

where does gas exchange btw lungs and blood take place?

Answer 58

alveolar and capilary walls

Question 59

how does CO2 leave the body?

Answer 59

CO2 diffuses across the respiratory membrane into the alveolus and is then expelled by respiration