L1 Intro Flashcards
Trachea Anatomy
10cm long
Larynx –> T4/5
C-shaped cartilage ring- keeps airway open as is only entry point for air
Trachealis- a) cough reflex, narrow airway to change pressures b) flexibility for bolus of food in posterior oesophagus
Trachea Histological appearance
Lumen: Respiratory epithelium (pseudo. col. epi. + goblet cells + basal cells)
Glands
Smooth muscle (not that much as not much effect on control of flow in that airway)
Cartilage
Trachea Function
Large open tube
-Conducting zone
Bronchus Anatomy
15 Generations of branching Cartilage plates: keep airway from collapsing Glands Non-continuous Smooth muscle Respiratory EPtihelium
Bronchus Histological appearance
Large Bronchi: Respiratory epi
Smaller Bronchi: Transition to columnar ciliated + goblet
Bronchus Function
- need to keep airways open in segmental + lobar bronchi
1) Conditioning
2) Branching
3) Transition (towards blood air barrier in alveoli)
Bronchiole Anatomy
1mm diameter (narrower + simpler) Last Bronchiole of C.Z.= Terminal Bronchiole
Bronchiole Histological Appearance
cuboidal ciliated epithelium
club cells
Smooth Muscle
-No Glands, cartilage or Goblet cells (not needed, airways so small that can control lumen size via smooth muscle only)
Bronchiole function
Smooth Muscle (contraction/relaxation) Controls flow into alveoli
Journey that air takes
Nasal cavity –> Pharynx –> Larynx –> trachea –> Bronchi –> Bronchioles –> Alveoli
- Protected by thorax/thoracic cage
- Left lung smaller due to heart
- massive surface area/very compact
Bronchial Tree
Trachea
- -> Primary/Main Left and Right Bronchus
- -> Lobar Bronchus
- -> Segmental Bronchus
- -> Terminal Bronchiole
- -> Respiratory Bronchioles
- -> Alveolar duct
- -> Alveolar sacs
- -> Alveoli
Functions of Respiratory System
- Protection against unsterile air
- Sound production (as air goes through larynx)
- Partial role in Blood Volume and pH control
Upper Respiratory Tract
Nasal Vestibule
Nasal Cavity
Pharynx
Lower Respiraotry Tract
Larynx
—>
Alveoli
Upper and Lower Respiratory Tract division
Anatomical divisions
clinical relevance re treatment
1) Upper R.T. Infection: infection isnt too dangerous. cold/pharyngitis. dont need aggressive antibiotics. fast resolving.
2) Lower R. T. I.
-less ability to defend against pathogens
- pneumonia/bronchitis
-dont resolve/fever/wheeze
Ear infection
eustachian tube
- excessive fluid draining into ears
- common in children
Functional divisions
- Conducting zone (Nasal cavity –> terminal bronchioles)
- NO gas exchange
- More complex: preparation for gas exchange - Respiratory Zone (Resp. Bronchiole –> Alveoli)
- Gas exchange
- greater SA
- rich capillary network
- last defense
Pseudostratified columnar ciliated epithelium
Location: Nasal cavity –> Bronchi
Function:
1) Ciliated: Mucociliary escalatory. motile cilia, beating and catching particles in carpet of mucus. move to back of throat to spit out
2) Protective: Tall cell for thick layer
Goblet cells
Location: Nasal cavity –> Bronchi
Function:
1) Mucus production: Acute (for infection/noxious substance/hayfever/smoking)
-stimulate quite response
Basal cells
Location: Base of BM basement Membrane Function: 1) Stem cell population -differentiate into Goblet cells and Pseudostratified Columnar Ciliated Epi. -sit on bottom
Brush cells
Location:
Function:
1) Sensory cells (produce nervous response upon insult)
Small Granule Cells
Location:
Function:
1) Endocrine cells (release e.g histamine. in response to toxin)
Club cells
a.k.a. Clara cells Location: Bronchioles Function: -Cuboidal. Non ciliated 1) secrete watery substance a) hydration b) antimicrobial secretions
Type 1 Pneumocytes
Location: Alveoli
Function:
-squamous (super skinny) - Flat and Thin Blood-Air Barrier/membrane
1) Increase SA in alveoli