Respiratory System Flashcards
two portions of respiratory system
conducting Portion: nasal cavities, Pharynx, Larynx, trachea, bronchi, bronchioles
Respiratory Portion: respiratory bronchioles, alveolar ducts, sacs, alveoli —-> pulmonary acinus
Nasal cavities
Vestibule
Respiratory area
Olfactory area
Respiratory area
with respiratory mucosa:
- pseudostratified
- lamina propria
The 6 cells of respiratory epithelium
Goblet Basal Ciliated Serous Brush Endocrine
Ciliated cells
- tall
- lots of mitochondria to provide ATP
- Traps matter and cleans air
Goblet cells
- apical part contains granules with mucinogen that forms mucus
Basal cell
- DO NOT REACH APICAL SURFACE
- gives rise to other cells
Serous cell
- columnar
- secretes serous secretion
Brush cell
- narrow columnar
- with tall microvilli
- have contact with sensory fibers on basal Surface
- sensory receptor
Endocrine cell
- small granules in basal part
- Contents secreted into blood and act on other cells
Lamina propria of respiratory mucosa in nose
loose CT
- highly vascularized erectile tissue: a lot of capillaries and veins for warming function
- mixed muco-serous Glands: provide mucus to huidify the air and trap dust
mucosa lies on periosteum/ - chondrium
Pharynx - three regions
Oropharynx –> stratified squamous
Nasopharynx –> respiratory epithelium
Laryngopharynx –> stratified squamous
Lamina propria of pharynx
loose CT
mucous Glands
lymph nodules!!
mucosa lies on musculature
Epiglottis
Elastic cartilage
stratified suqamous non-keratinizing AND respiratory
lamina propria with muco-serous glands
Laryngeal mucosa
respiratory Epithelium (vocal cord --> stratified suqamous) lamina proprie with muco-serous Glands
mucosa lies on laryngeal cartilages, ligaments and musculature –> are all hyaline cartilages
Wall structure or trachea and bronchi
Mucosa:
- Epithelium
- lamina propria
- lamina muscularis
Submucosa
Cartilaginous layer!!!
Adventitia
Developmental sources
Epithelium: from endoderm
Other tissues: from mesoderm
Mucosa of trachea
respiratory Epithelium on b.m.
lamina propria with lymphatic nodules (no Glands)
lamina muscularis
Submucosa of trachea
loose CT
sero-mucous Glands
lymphatic nodules
Cartilaginous layer of trachea
- 16-20 C shaped rings of hyaline cartilage
- posteriolry: rings are connected by trachealis muscle
- dense CT between rings
Bronchial wall compared to trachea
Chips of cartilage instead of rings
no lymphatic nodules
Bronchial tree
Main bronchi
Lobar bronchi
Segmental bronchi
Structural changes of the brochial tree
Epithelium: pseudostratified –> simple columnar
less goblet cells
less Seromucous Glands
less cartilage
Mucosa of Bronchioles
- respiratory –> simple cuboidal ciliated –> non-ciliated
- Ciliated cells replaced by CLARA CELLS
- lamina propria
- lamina muscularis: smooth mscuel increases
no cartilage
no Glands
no goblet cells
Clara/club cells
in mucosa of bronchiole
- columnar cells
- domed apices
- short microvilli
- apical cytoplasm with secretory granules
Functions of Clara cells
- secrete Surface active Agent
- secrete CC16
- detoxify inhaled Toxins
- act as stem cells
Pulmonary acinus
Respiratory bronchioles
Alveolar ducts
Alveolar sacs
Alveoli
Respiratory bronchioles
first alveoli arise from their wall
terminate in alveolar ducts
Alveolar duct
linear Arrangements of alveoli
through atria leads to alveolar sacs
Alveolar sac
Space which opens into several alveoli
Alveoli
- area for gaseous Exchange
- spimle squamous Epithelium with type I and II penumocytes
- Alveolar Septum between alveoli
- Alveolar pores: Openings in alveolar septa
Type I pneumocyte
- squamous
- organelles around flat nucleus
- joined to other cells by tight junctions
- part of blood-air-barrier
- for gas exchange
Type II pneumocyte
- large and round
- cytoplasm with vesicles of surfactant
- synthesized and secretes surfactant
- can differentiate into type I after damage
Surfactant
- Phospholipids, carbohydrates, proteins
- reduces Surface Tension
- traps Bacteria and viruses
Alveolar macrophages
- from monocytes
- in alveolar Septa
- migrate between type I cells
- phagocytose dust and bacteria
Blood-air-barrier (respiratory membrane)
- Endothelium of capillary
- Fused Basement membranes of cap. and alveoli
- Type I pneumocyte
- Surfactant