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Flashcards in Anatomy: respiratory system Deck (59):
1

What are the two main functions of the respiratory system? What is the border between the upper and lower respiratory tract?

Air distribution and gas exchange

The larynx (upper: nasal cavity, paranasal air sinuses, pharynx, lower: larynx, trachea, main bronchi, lungs)

2

What are the main functions of the thorax?

Housing and protection of vital organs and breathing
Thorax = thoracic wall and thoracic cavity

3

What are the main body cavities of the trunk?

Thoracic
Abdominal
Pelvic

Diaphragm = boundary between thoracic and abdominal cavities

Thoracic cavity (enclosed by thoracic wall) - subdivided into 3 main spaces mediastinum and two pleural cavities (lateral - surround the lungs)

4

What are the main organs of the mediastinum?

heart and great vessels:
Aorta emerges from left side then passes inferiorly as thoracic aorta
Pulmonary trunk gives off two pulmonary arteries that enter the lungs
Superior vena cava visible right of pulmonary trunk

Posterior to heart, trachea bifurcates into right and left main bronchi
Oesophagus (runs through entire length of thorax)

5

What is the function of the nasal cavities?

Filtering, warming, and moistening of incoming air

6

What are nares?

External nares (nostrils): paired openings - inferior surface of external nose, surrounded by rigid, short hairs; prevent large airborne particles from entering nasal cavity

Internal nares (choanae): link nasal cavity with pharynx

7

What are paranasal air sinuses?

Air spaces in bones of skull (named after bones that they are located) - surround nasal cavities
Lined with ciliated columnar epithelial, continuous with lining of nasal cavity

grow as outpouchings of nasal cavity into neighbouring bones - communicate by openings into nasal cavity

all small at birth, enlargement begins around 6-7 years go age - considerable enlargement particularly in maxillary - important factor in change of facial features at puberty

Sphenoidal
Frontal
Maxillary
Ethmoidal air cells

8

What exists on the lateral wall of the nasal cavity?

Nasal conchae - shape functionally significant as they form turbulences of air (warming, moistening, cleaning)

Meatus beneath each concha - receive openings of the paranasal air sinuses and

9

What exists on the lateral wall of the nasal cavity?

Nasal conchae - shape functionally significant as they form turbulences of air (warming, moistening, cleaning)

Meatus beneath each concha - receive openings of the paranasal air sinuses and the nasolacrimal (tear) duct

10

What role do tear glands play?

Tears from lacrimal sac → nasal cavity → drain into inferior nasal meatus → nose running
(conditioning of incoming air?)

11

What is the olfactory region?

Located in upper, posterior part of nasal cavity
Only a few centimetres wide, contains over 100 million olfactory receptor cells

Roof of cavity = where nerves form olfactory nerve

12

What exists on the lateral wall of the nasal cavity?

Nasal conchae - shape functionally significant as they form turbulences of air (warming, moistening, cleaning) → superior, middle and inferior

Meatus beneath each concha - receive openings of the paranasal air sinuses and the nasolacrimal (tear) duct

13

What is the pharynx?

Connecting pathway between the nasal cavities and the larynx - serves as common pathway for respiratory and GI systems

Nasopharynx: posterior to nasal cavity, Oropharynx: posterior to oral cavity, Laryngopharynx: posterior to larynx

Auditory tube opens into the lateral wall of the nasopharynx
Soft palette = junction between nasopharynx and oropharynx

14

What is the pharynx?

Connecting pathway between the nasal cavities and the larynx - serves as common pathway for respiratory and GI systems

Nasopharynx: posterior to nasal cavity, Oropharynx: posterior to oral cavity, Laryngopharynx: posterior to larynx

Auditory tube opens into the lateral wall of the nasopharynx

15

What is the pharynx?

Connecting pathway between the nasal cavities and the larynx - serves as common pathway for respiratory and GI systems

Nasopharynx: posterior to nasal cavity, Oropharynx: posterior to oral cavity, Laryngopharynx: posterior to larynx

16

What is the auditory tube?

opens into the lateral wall of the nasopharynx

17

What is the auditory tube?

opens into the lateral wall of the nasopharynx

pressure equalisation: opens to let small amount of air through, equalises between middle ear and atmosphere - mucous drainage from middle ear

18

What are the tonsils?

Palatine tonsils; each side at junction between oral cavity and oropharynx

Pharyngeal tonsil; posterior wall of nasopharynx

Produce antibodies which trap germs when breathing in

19

What is the pharynx?

Connecting pathway between the nasal cavities and the larynx - serves as common pathway for respiratory and GI systems

Nasopharynx: posterior to nasal cavity, Oropharynx: posterior to oral cavity, Laryngopharynx: posterior to larynx

Mucosa lining the oropharynx and laryngopharynx different than that lining the nasopharynx (Pseudostratified ciliated columnar epithelium with goblet cells, also stratified squamous) because nasopharynx same as nasal cavity (cleans, warms, moistens) - other 2 = digestive tract - stratified squamous

20

What is the larynx?

Several irregularly shaped catilages attached to each other by synovial or cartilaginous joints, ligaments, membranes and muscles

Vocal folds overlie vocal ligaments, by muscles moving the cartilages to which the ligaments are attached → changes in pitch of voice

21

What is the larynx?

Several irregularly shaped catilages attached to each other by synovial or cartilaginous joints, ligaments, membranes and muscles

Vocal folds overlie vocal ligaments, by muscles moving the cartilages to which the ligaments are attached → changes in pitch of voice

Larynx suspended on small U-shaped hyoid bone
Muscles attached to this bone help control action of larynx

22

What are the main cartilages of the larynx?

Thyroid: large, palpatable

Cricoid: signet-ring shaped

Arytenoids: 2, posterior, insertion point for vocal ligaments. muscles moving arytenoids are innervated by branches of the vagus nerve

Epiglottis: moves forwards and backwards to prevent food entering lower respiratory tract by closing the laryngeal inlet

23

What are the main cartilages of the larynx?

Thyroid: large, palpatable

Cricoid: signet-ring shaped

Arytenoids: 2, posterior, insertion point for vocal ligaments. muscles moving arytenoids are innervated by branches of the vagus nerve

Epiglottis: moves forwards and backwards to prevent food entering lower respiratory tract by closing the laryngeal inlet (when swallowing - larynx moves up; closes entry to trachea)

24

What are the three portions of the laryngeal cavity?

Vestibule: above the vestibular folds
Ventricle: between vestibular and vocal folds
Infraglottic cavity: below vocal folds

25

What are the three portions of the laryngeal cavity?

Vestibule: above the vestibular folds (false vocal folds)
Ventricle: between vestibular and vocal folds (true VFs)
Infraglottic cavity: below vocal folds

26

What is the function of the vocal folds?

protect airway from choking on material in the throat
regulate flow of air into lungs
production of sound used for speech

27

What is the function of the vocal folds?

protect airway from choking on material in the throat
regulate flow of air into lungs
production of sound used for speech

28

What are the main cartilages of the larynx?

Thyroid: large, palpatable

Cricoid: signet-ring shaped, attachment for muscles and ligaments involved in opening/closing airway and speech production

Arytenoids: 2, posterior, insertion point for vocal ligaments. muscles moving arytenoids are innervated by branches of the vagus nerve

Epiglottis: curved, bound anteriorly to the opening of the larynx (laryngeal inlet) - moves forwards and backwards to prevent food entering lower respiratory tract by closing the laryngeal inlet (when swallowing - larynx moves up; closes entry to trachea)

29

What is the trachea?

Continuous with larynx, consists of approx 15-20 C shaped hyaline cartilage rings
Open part of C faces posteriorly - room for oesophagus to expand as swallowed food passes to the stomach

Between the two ends of each ring; smooth muscle, trachealis muscle (trachealis muscle - contracts during coughing so air expelled with more force)

Birfucates into two primary bronchi - important clinical landmark: v-shaped cartilage called carina at bifurcation

30

What are the bronchi / bronchial tree?

Right and left pulmonary bronchi: left primary bronchus is longer and enters lung at lower level (foreign objects usually in right bronchus as wider and shorter)

Primary = pulmonary
Seconday = lobar
Tertiary = segmental

Each enters the lung root (bronchi enter lung in the hilium, posterior to the vessels - pulmonary veins and arteries) to divide into lobar (secondary) bronchi

Within the substance of the lung, lobar bronchi divide to segmental (tertiary) bronchi

Trachea and bronchi in constant state of movement

31

What are the bronchi / bronchial tree?

Right and left pulmonary bronchi: left primary bronchus is longer and enters lung at lower level (foreign objects usually in right bronchus as wider and shorter)

Each enters the lung root (bronchi enter lung in the hilium, posterior to the vessels - pulmonary veins and arteries) to divide into lobar (secondary) bronchi

Within the substance of the lung, lobar bronchi divide to segmental (tertiary) bronchi

Trachea and bronchi in constant state of movement

32

How are the lungs structured?

Oblique fissure: upper and lower lobes
Horizontal fissure: right lung - separates middle and upper

Left lung: two lobes, upper lobe has cardiac notch on anterior border - lower part of notch projects as lingula (tongue-like)

Segment of lung tissue supplied by tertiary bronchus =

33

How are the lungs structured?

Oblique fissure: upper and lower lobes
Horizontal fissure: right lung - separates middle and upper

Left lung: two lobes, upper lobe has cardiac notch on anterior border - lower part of notch projects as lingula (tongue-like)

Segment of lung tissue supplied by tertiary bronchus = bronchopulmonary segment

34

How are the lungs structured?

Oblique fissure: upper and lower lobes
Horizontal fissure: right lung - separates middle and upper

Left lung: two lobes, upper lobe has cardiac notch on anterior border - lower part of notch projects as lingula (tongue-like)

Segment of lung tissue supplied by tertiary bronchus = bronchopulmonary segment (names correspond to direction that segmental bronchi take) - diseased one may be removed without affecting neighbouring segments

Postural drainage of fluid filled segments in cystic fibrosis or infection

35

Describe the bronchopulmonary segments

Roughly pyramidal, tertiary bronchus enters apex of pyramid - after entering segment it divides progressively eventually reaching respiratory bronchioles and alveoli

36

How are the lungs positioned in the body?

Apex projects into root of neck
Base fits into dome of diaphragm

Right lung vertically shorter than left as the right dome of the diaphragm is higher [right lobe of liver is bigger] (but it is also larger - left lung smaller as cardiac notch makes space for heart)

37

What is a pulmonary lobule?

Respiratory or functional unit of the lung - separated from others by the connective septum

Each consists of many acini (3-5 alveolar sacs)
Each alveolar sac = smallest collection of alveoli
Alveolar duct = space within alveolar sacs

38

What happens to the tertiary bronchi? (segmental)

Progressive divisions → finer divisions (about 20)
Irregular hyaline cartilaginous plates and smooth muscle in wall of bronchi → cartilaginous plates disappear in passages less than 1mm in diameter

These are bronchioles → only spirally arranged smooth muscle fibres in their walls

39

What are alveoli?

Thin walled air spaces lined with simple squamous epithelium - related to pulmonary capillaries in alveolar walls

Connective tissue of alveolar walls between alveoli contains elastic tissue and phagocytes

40

What is a pulmonary lobule?

Respiratory or functional unit of the lung - separated from others by the connective septum

Venule located in interlobular septum - carries high oxygenated blood to heart

Each consists of many acini (3-5 alveolar sacs)
Each alveolar sac = smallest collection of alveoli
Alveolar duct = space within alveolar sacs

41

What are alveoli?

Thin walled air spaces lined with simple squamous epithelium - related to pulmonary capillaries in alveolar walls → arteriole accompanies respiratory pathways, branches and forms capillary network around alveoli (provides low oxygenated blood)

Connective tissue of alveolar walls between alveoli contains elastic tissue and phagocytes

42

What is a pulmonary lobule?

Respiratory or functional unit of the lung - separated from others by the connective septum (fibrous connective tissue)

Venule located in interlobular septum - carries high oxygenated blood to heart

Each consists of many acini (3-5 alveolar sacs)
Each alveolar sac = smallest collection of alveoli
Alveolar duct = space within alveolar sacs

43

What happens to the tertiary bronchi? (segmental)

Progressive divisions → finer divisions (about 20)
Irregular hyaline cartilaginous plates and smooth muscle in wall of bronchi → cartilaginous plates disappear in passages less than 1mm in diameter

These are bronchioles → only spirally arranged smooth muscle fibres in their walls

Bronchus that enters a tip of the lobule immediately loses its cartilage → bronchiole

44

What is the diaphragm?

Musculo-tendinous sheet that separates the thoracic and abdominal cavities

Attached to inferior internal surface of rib cage via 2 muscular bands: crura (left and right crus) to superior lumbar vertebrae

45

What are the pleural cavities?

One of three serous cavities in the body

46

What are the pleural cavities?

One of three serous cavities in the body (left and right)

Two closed sacs of serous membrane (pleura); moist due to small amount of pleural fluid - reduces friction between the apposed surfaces

47

What are the pleural cavities?

One of three serous cavities in the body (left and right)

Two closed sacs of serous membrane (pleura); moist due to small amount of pleural fluid - reduces friction between the apposed surfaces subject to movement

Contain negative pressure - keeps lungs inflated against their natural tendency to collapse due to elastic tissue

Potential spaces - when air accidentally enters them, lung partially collapses (pneumothorax)

48

What are the pleural cavities?

One of three serous cavities in the body (left and right)

Two closed sacs of serous membrane (pleura); moist due to small amount of pleural fluid - reduces friction between the apposed surfaces subject to movement

Contain negative pressure - keeps lungs inflated against their natural tendency to collapse due to elastic tissue

Potential spaces - when air accidentally enters them, lung partially collapses (pneumothorax)

49

What are the layers of the pleura?

Parietal pleura: layer that lines thoracic wall
Visceral pleura: layer that covers the lung

Continuous with eachother around helium of lung

Parietal pleura - different names:
Costal - adheres to thoracic wall
Diaphragmatic - apposed to diaphragm
Mediastinal - lines the mediastinum
Cervical - extends superiorly into neck reaching level of posterior end of first rib

50

What are the pleural recesses?

Lungs do not completely fill pleural cavities (allows for expansion) → recesses where two layers of parietal pleura are in contact - in quiet inspiration, anterior border of lung does not extend as far medially as the anterior border of the pleural cavity: costamediastinal recess (where cardiac notch is)

51

How are the pleura supplied by nerves?

Receive sensory input from structure it covers

Visceral pleura innervated by ANS (not sensitive to normal painful stimuli such as cutting)

Parietal pleura - innervated by intercostal nerves and phrenic nerves - sensitive to normal painful stimuli

Referred pain from parietal pleura covering diaphragm is felt over should tip - phrenic nerve also supplies skin at shoulder

52

What are the pleural recesses?

Lungs do not completely fill pleural cavities (allows for expansion) → recesses where two layers of parietal pleura are in contact → provide spaces where fluid can collect and from which can be aspired

costomediastinal recess: (where cardiac notch is - located anteriorly where costal pleura becomes mediastinal pleura, overlies heart): in quiet inspiration, anterior border of lung does not extend as far medially as the anterior border of the pleural cavity

costodiaphragmatic recess (located inferiorly where costal pleura becomes diaphragmatic pleura): inferior border of lung does not extend as far as the inferior border of the pleura in normal respiration

53

How are the pleura supplied by nerves?

Receive sensory input from structure it covers

Visceral pleura innervated by ANS (not sensitive to normal painful stimuli such as cutting)

Parietal pleura - innervated by intercostal nerves and phrenic nerves - sensitive to normal painful stimuli

Referred pain from parietal pleura covering diaphragm is felt over should tip - phrenic nerve also supplies skin at shoulder

54

What is pneumothorax?

Presence of air or gas in pleural cavity which can impair oxygenation or ventilation

Can cause shortness of breath

Tension pneumothorax: mediastinum shifts, trachea moves away from the side of tension

55

What is pneumonia? What anatomical features may delay spread of infection in lung?

Any infection of lung parenchyma - bacterial pneumonia has two patterns of anatomical distribution

Lobar bronchopneumonia: patchy consolidation of lung
Lobar pneumonia: consolidation of a lobe (or a large part of it)

Pleura
Connective tissue membranes
Space separating lobes

56

What is pleurisy?

Overlying pleura shows dull yellowish exudates - extravascular fluid with high protein and cell composition

Pleural exudates that are shaggy and purulent = lots of leukocytes, cell debris and microbes

Exudate = inflammatory, transudate = due to high hydrostatic pressure (low protein content)

Symptoms: shortness of breath, fever, cough, chest pain outside airways - especially when breathing in

57

What is lung cancer? What symptoms can occur if the tumour is in the apex of the left upper lobe?

most common cancer worldwide, variety of benign and malignant tumours may arise in lung but 90-95% are carcinomas - may be primary or secondary tumours, often secondary tumours are multiple

weakness of intrinsic muscles of the hand - compression/irritation of brachial plexus

58

Suface anatomy: apex of the lung, anterior borders of lung

apex: above medial third of clavicle

right lung: continues inferiorly to 6th costal cartilage

left lung: diverges laterally at 4th rib, continues to deviate posterior to 6th rib [cardiac notch posterior to 5th and 6th costal cartilages] - space, particular at 6th intercostal space = room for needle at side of sternum to drain pericardial cavity (pericardial effusion) without going through lung tissue/pleural cavity

59

Surface anatomy: lower borders of the lung

Midinspiration: begins from 6th costal cartilage in midclavicular line, posteriorly across 8th rib in midaxillary line, 10th rib posteriorly (level of spine of T10)

In extremes of respiration has excursion of 6-7cm