what are the functions of the respiratory system (respiration)?
what are the functions of the respiratory system (not respiration)?
regulation of blood pH
voice production
olfaction
innate immunity
voice production?
air movement past the vocal cords
olfaction?
airborne molecules are drawn into the nasal cavity
innate immunity?
protects against certain micrroganisms and other pathogens- preventing them from enetering the body and by removing them from respiratory surfaces
what are the structures in the upper respiratory tract?
nose and nasal cavity
pharynx (throat)
larynx
what are the structures of the lower respiratory tract?
trachea
bronchi
lungs
what are the characteristics of the lungs?
Within the thoracic cavity
2 lungs
* separated by the mediastinum in which the
heart is situated
Each lung is divided into lobes
* Left lung – 2 lobes (upper and lower)
* Right lung – 3 lobes (upper, middle and lower)
Heart sits within the ‘cardiac notch’
* so the left lung slightly narrower
Each lung: Surrounded by
a pleural cavity
* formed by 2 pleural
membranes
* the visceral and parietal
pleurae
Passages branch
* Decrease in size
* Increase in number
what is the seperation of the bronchial tree?
what are the characteristics of the bronchial tree?
Top of tree
* Lots of cartilage some smooth muscle
* Keep airways open
Bottom of tree
* Lots of smooth muscle less cartilage
* Change diameter of airways
where is the respiratory zone?
alveoli
* Air filled sacs
* Membrane v elastic* Expand / contract
* Surrounded by a capillary network to provide efficient gas exchange
* The respiratory membrane
* where gas exchange between the air and
blood takes place
* Very very thin
what are the roles of type 1 alveolar cells?
Type I alveolar cells (95%) form
the alveolar wall,
* permit gas exchange
what are the roles of type 2 alveolar cells?
Type II alveolar cells secrete
surfactant
* Defence
* Role in breathing and stabilises
alveoli (surface tension)
* Recoil of lungs
what are the roles of alveolar macrophages?
defence against foreign particles/infectious
microorganisms that reach the alveoli
what are the two phases of ventillation?
how is ventillation regulated?
what way does ai flow?
from an area of high pressure to low pressure
what are the respiratory muscles?
what are the characteristics of the diaphragm?
what are the charcateritics of intercoastal muscles?
what is happening to the muscles while inspiration is happening?
what is the active process of inspiration?
signals from the respuratory cavity in the medulla oblongta (brain stem) –>
contraction of the diaphram and intercostal muscles leading to the diaphram moving downward –>
transverse expansion of thoracic cavity+ vertical expansion of thiracic cavity –>
lung volume increases and the intra-alveolar pressure decreases –> air-sucked in
what is happening to the muscles while expirating?
what are the air flow and pressure changes in inspiration?