4. respiratory system Flashcards
functions of respiratory system
- respiration
- blood ph regulation
- sound production
- olfaction
- protection
nasal cavity
passageway for air
- hair filters particles
- mucus traps dust
pharynx
throat, passage for food and air
- nasopharynx, oropharynx, laryngopharnyx
larynx
voice box; passageway for air moving from pharynx to trachea; contains vocal cords
trachea
windpipe
Cleansing of air breathed in
Facilitate ease of peristaltic movement in esophagus
Keep airway open
bronchial tree
primary bronchi, secondary bronchi, tertiary bronchi, bronchioles, terminal bronchioles
lungs
located in thoracic cavity
Heart is located on the left side which decreases the size of the left lung
The right lung appears shorter due to the presence of the liver
- right lung has three lobes and separated by 2 fissures, 1 primary bronchi and 3 secondary bronchi
- left lung has 2 lobes and separated by 1 fissure, 1 primary bronchi and 2 secondary bronchi
characteristics of respiratory membrane
thickness - thin membrane increase rate of movement of gases
surface area - high surface area increased volume of gas exchange
diffusion coefficient - how easily a gas can diffuse in and out
partial pressure - pressure exerted by each gas in a mixture of gases
moist membranes - gases dissolve in the fluid helping them to diffuse
O2 transport
- travels in the blood haemoglobin
from alveoli to blood
from blood to tissue
CO2 transport
bound to haemoglobin
- form blood to alveoli
- from tissues to blood
external respiration
- gas exchange between alveolar air spaces and alveolar capillaries
- gases move from higher partial pressure to lower partial pressure
internal respiration
as exchange between tissue capillaries and tissues across capillary walls
- gases move from higher partial pressure to lower partial pressure
pleura
Lung is encased in the pleura which consists of a parietal layer and visceral layer
Parietal layer lines the thoracic wall and the visceral layer lines the surface of the lungs
Two layers are separated by pleural fluid
Pleural fluid has 2 functions
Acts as a lubricant allowing the parietal and visceral pleura to slide past each other as the lungs and thoracic wall move
Helps hold the parietal and visceral pleura together
Quiet breathing
inspiration involves muscular contractions and expiration is passive
active breathing
expiratory muscles become active and are stimulated to contract
movement of air into lungs
Nasal cavity - pharynx - larynx - trachea - primary bronchus - secondary bronchus - tertiary bronchus - bronchiole - terminal bronchiole - respiratory bronchiole - alveolar duct - alveoli
Alveolar ventilation
volume of air available for gas exchange per minute
Tidal volume
he amount of air inspired or expired with each breath
Inspiratory reserve volume
the amount of air that can be inspired forcefully after inspiration of tidal volume
Expiratory reserve volume
the amount of air that can be forcefully expired after expiration of tidal volume
Residual volume
the volume of air remaining in the respiratory passages and lungs after the most forceful expiration
Pulmonary capacities
the sum of two or more pulmonary volumes
Inspiratory capacity
the amount of air a person can inspire and maximally after normal expiration (tidal volume + inspiratory reserve volume)
Functional residual capacity
the amount of air remaining in the lungs at the end of a normal expiration (expiratory reserve volume + residual volume)
Vital capacity
the maximum volume of air that can be expelled form the respiratory tract after maximum inspiration
Total lung capacity
inspiratory reserve volume + expiratory reserve volume + tidal volume + residual volume
Respiratory rate
number of breaths taken per minute
Minute ventilation
total amount of air moved into and out of the respiratory system each minute
Anatomic dead space
space formed by nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles and terminal bronchioles
Forced vital capacity
maximal volume of air that can be forcefully expired as fast as possible after a deep breath in
Forced expiratory volume in 1 second
the volume of air expired in the first second of the test
Why would your lungs collapse if you were stabbed in the chest?
Stabbing puts pressure into the intrapleural space from the lungs causing the lungs to collapse due to intrapleural pressure increasing more then the intra alveolar pressure
Why do we breathe faster during and after exercise?
During exercise we require more energy, oxygen and need more waste to be removed
After exercise we have created an oxygen debt and need to repay the oxygen back, extra oxygen is required to metabolise lactic acid and replenish ATP
Dynamic lung function
lung volume measured in relation to time
Dependent on rate of flow of air
Usually determined during repetitive breathing
Essential for diagnosis of obstructive lung disease
Static lung function
independent of rate of air flow
Determined during one maximal inspiration and or expiration
Pulmonary ventilation
process or moving air into and out of the lungs
Boyles law
as volume increases pressure decreases
What are the roles of the conchae and meatus
To increase the surface area of the nasal cavity, create more turbulent air flow and increase the likelihood that air will come into contact with the mucous membrane of the nasal cavity
How does the nasal cavity warm and humidify air
As air passes over the mucous membrane lining the nasal cavity the mucous produced increases the moisture of air. The air is warmed to body temp by the capillaries close to the surface in the nose which carry warm blood
Conductive respiratory parts
trachea, bronchi, bronchioles, terminal bronchioles
Respiratory parts
- respiratory bronchioles, alveoli
