2.4 Respiritory System Flashcards
Resp system (2) basics
Produces sound, site for olfactory sensation (nose) olfactory mucosa
Gas conditioning? (3)
Warmed to body temp.
Humidified
Cleared of particles/matter
Conducting and respiritory portion?
Conduct - ext to Lungs - nasal cavities, pharynx, larynx, trachea, main bronchi
Int to lungs - bronchial tree to TB
Respiritory portion - RB - Alveoli
Nose (5)
Provides airways, moistens + warms air, filters air, resonating chamber for speech, olfactory receptors
Nasal cavitiy. Passes thru. Roof. Floor. Connects.
Passes thru nares
roof= olfactory mucosa (psuedostratified)
Floor=anterior hard, post soft palate
Nasa, septum- perpendicular plate (ethmoid, vomer, septal cartilage)
Connects pharynx post thru choanae (post nasal aperture)
Olfactory mucosa? (2)
Bowman’s glands,
First cranial nerve in olfactory nerves
Paranasal sinuses name 4 and (2)
Maxillary, ethmoidal, sphenoidal, frontal
Air warming and moistening Open into nasal cavities Lighten skull Infected : sinusitus Lined by same mucosa as nasal cavities
Nasal cavity - ciliated psuedostratified columnar epithelium 5 cell types
Ciliated - tall columnar with cilia - project into mucus covering surface if epithelium
goblet - mucus secretion
Basal - stem cells
Brush - cells in resp tract - short blunt microvilli
Small granule cells (kulchisky cells) - secretory granules - apud system cells
Olfactory region of nasal cavity. Types of cells (4). Nerves.
Specialised olfactory mucosa, olfactory bowmans glands
Epithelium : olfactory receptor cells, supporting cells (mechanical and met support), basal cells, brush cells
Unmylinated nerves in lamina propria
Olfactory receptor cells?
Bipolar neurons, apical cilia non motile.
Collections of axons from receptor as bundles - thru cribiform placte of ethmoid bone - dura, archanoid, pia mater to olfactory bulb
1 month lifespan
Anosmia - loss of smell
Olfactory glands (5) name. Type. Appearance. Epi. Secretion
Bomans glands
Branched tubuloalveolar serous
Combo of lipofuscin give yellow brown appearance.
Cuboidal cells
Secretion - trap and solvent for odiferous substances - bind to receptor - amp camp calcium na channels depolarisation
Pharynx (3)
Cranial to c6 - 15cm - nol
Lymphatic nodules - junc sup post wall - pharyngeal tonsil
Passageway for food and resonating chamber for speech
What connects nasopharynx to middle ear?
Eustachian tube
Larynx
And 3 function
c4-6.
Passage of air - opening of lumen
Functions : vocalisation, provides an open airway, switching mechanism - food and air into proper channels
Cartilages of larynx (8) connect by?
Connected by membrane and ligaments
Thyroid - laryngeal prominence - adams aple
Circoid - - inf to thryoid cart - only complete ring of csrtilage : signet ring shaped
Pairs of small cart, post :
Arytenoid
Corniculate
Cuneiform
What is the 9th cartilage of larynx
Epiglottis elastic
What is deglutition?
Swallowing
Larynx structural areas? (4)
Supra/infra glottic space
True/false vocal chord - ligaments
Ventricles of larynx
Rima Glottis
True vocal chord : muscles - contraction + movement - vocalisation
False (1) and true vocal chord (2)
Factors determine sound (3)
False vocal chord - superior ligaments - vestibular folds
True vocal chord - inf ligaments - vocal folds
- tension, length + position of vocal folds determine quality of sound
Structure of larynx
Mucosa - pseudostrat cilia , goblet cells, ss on vocal chords, lamina propria. Lymph nodes.
Muscles of larynx - intrinsic : striated muscle acting on true vocal chords, regulation of glottis - influence quality of sound
Extrinsic
Trachea diameter, length. Rings, inspiration/expiration, flexible, carina,
Diameter : 2.5
Length : 10
16-29 c shaped rings (hyaline cartilage) - joined by fibroelastic ct ( inspiration - expansion and extension, expire - passive recoil)
Flexible for bending : remain open despite pressure changes during breathing
Carina - branching of trachea into bronchi
Trancheal rings and skeleton
Where cartilage not present - sm cells - tracheal muscle
Skeelton - fibroelastic ct, support mucosa - prevent collapse during inspiration.
Why is left bronchus shorter?
Due to heart
Wall of trachea layers?
Mucosa - cliliated ps epi. Elastic, fiber rich lamina propria
Submucosa - more dense ct than lp
Cartilaginous layer - c shaped hyaline cart
Adventitia - ct bind trachea to adjacent structure
Quick facts about trachea? (4)
Unusually think bm - collagen and reticular fibres - dense
MucoCillary excalator by ciliated cells(200/cell) - remove small inhaled particles from lungs
Granule cells (kulchitsky cells) - enteroendocrine - some form associated with nerves -> neuroepithelium bodies - function in reflexes involving airway or vascular caliber
Tubuloacinar mixed glands
Trachea Boundary between mucosa and submucosa?
Elastic membrane
Submucosa not typical - loose character - BALT
Tracheal cart and muscle seperate?
What does adventitia contain?
Submucosa from adventitia
Adventitia contain - largest bv and nerves - supply tracheal wall, largest lymphatics
Trachea K cells. Where any they near? And precursor of ?
Near bm, precursor of small cell ling carinoma
Trachea - cartilage surrounded by (2)
Dct and elastic fibres
Main bronchi vs trachea? (Very similar)
Main bronchi: epi tell tall, fewer goblet cells, more elastin in lp, sm between lp and submucosa. Fewer glands in submucosa
Cartilage from rings to plates
Difference between right and left bronchi?
Right shorter - 3 lobes
Bronchi segments of L and R
Left bronchus - 2 lobar bronchial branches - 8 bronchopulmonary segments
Right bronchus - 3 “” - 10 “”
What is a bronchopulmonary segment ?
Segmental bronchus and lung parenchyma it supplies
Each with own blood supply , ct septa,
How can bronchi be identified and layers (5)
Cartilage plates and sm circ in muscularis mucosa - cart decrease sm increase
Mucosa ps epi, smaller lp in proportion to lumen
Muscularis - circ sm
Submucosa - lct, glands and adipose tissue
Cartilaginous
Adventitia - moderate dct, continuous with artery and lung parenchyma
Bronchioles and branching
Diameter
Bronchopulmonary segments -> pulmonary lobules - acini.
Each acinus - term bronchiole, resp bronchiole
1mm or less
In bronchioles there are not present but present in bronchi? (2)
Cartilage plates and glands
Small bronchioles epi. Terminal bronchioles which cells? Along length of bronchioles what increases
Simple cuboidal.
Term bronchioles -> clara cells among ciliated cells.
Along length of bronchiole - clara cells increase. Ciliated cells decrease.
Clara cells (4) general. Internal structure
Non ciliated. Rounded or dome shaped.
Rer, ser, lateral golgi apparatus, secretory granules.
Lipoprotein - surface active agent - prevent luminal adhesion to wall.
16kda - ccsp - clara cell secretory protein
Which part of bronchioles allow gas exchange and air conduction? What type of epithelium here?
Respiratory bronchioles- cuboidal epi
Alveoli
75m^2 sa. 150-200m in each lung. Site for gas exchange.
Alveolar ducts - no walls, alveoli at peripheries - rings of sm in inter-alveolar septa (also thin ct with capp)
Alveolar sacs - spaces surrounded by cluster of alveoli
Alveolar epithelium. 3 types of cells. 2 extra points
Type 1 alveolar cells (t1 pneumocytes) - squamous, thin. 40% no. 95% sa - occluding junctions - no cell division
T2 - cuboidal a 60%no. 5% sa. Lamellar bodies - secrete surface active agent - surfactant. Progenitor cells for t1 cells. (Extra
: hyper plasia and marker)
Brush cells - few in no. Receptor function - monitor air quality
T2 cells - surfactant
Reduce surface tension and clearance of foreign mat.n
Fetus after 35th week
Modulated by cortisol, insulin, prolactin, thyroxine
Less surfactant - premature infants - lung collapse - resp distress syn
Surfactant proteins
A most abundant. Surfactant homeostasis. Modulate immune response
B lamellar body - thing film of surfactant. Spreading onto epithelium of lung
C similar function to a B
D primary protein - involved in host defence - bind to microorganism and lymphocytes
Alveolar septeum. Thinnest barrier contains
.
Air blood barrier.
Thinnest barrier - thin layer of surfactant. T1 cell + basal lamina. capp endothelial cell + basal lamina. Fused BL.
CT cell and fibres in thick portion. Tissue fluid accumulates, drained by LV In term bronchioles
Alveolar macrophages
Present in ct and air space of alveolus.
Remove inhaled particles (air spaces) and rbc (septum)
Air space - scavenge surface therefore named dust cells
Rbc may enter alveolus - during heart failure
Alveolar pores of kohn
Allow air passage between alveoli.
Benefit during pathological conditions - normal pathway block - similar to anastomoses
Lungs blood supply
Rv - pulmonary art - pulmonary circ - capp - pulmonary venous circ - pulmveins - lv
Bronchial circ - aorta - bronchial art (all lung except alveoli). Finest branches anastomose with pul capp - Respiratory and conduction junction.
Bronchial veins drain ct of hilar region.
Lungs lv? (3)
Parallel to blood supply. 2 sets
1 drain parenchyma of lung -> the hilum - lymph nodes found here
2 drain surface of lung , travels ct of visceral pleura.
Visceral pleura of lung?
Serous membrane - surface mesothelium. Underlying ct
Lungs nerves
What are they involved in?
Sympathetic, parasympathetic of autonomic nervous system.
Sm in airway passages - control size/diameter of lumen
