Introduction and Anatomy of Respiratory system Flashcards
What are the functions of the respiratory system ?
Gas exchnage - O2 added to blood, CO2 removed
Acid base balance- regulation of body pH
Protection from infection
Communication via speech
Why is gas exchange important ?
needed to produce energy by using O2 and disposing of CO2 (waste product)
What is the respiratory system important for ?
Getting O2 into the body and CO2 out
Why is the integration of the respiratory and cardiovascular systems important ?
Allow the ability of tissues to transform fuel stored as chemical energy to physical energy
Deliver fuel to activate cells within tissues and remove waste products
What links the respiratory and cardiovascular systems ?
Gas exchange
What is cellular/ internal respiration ?
Biochemical process that releases energy from glucose
Latter requires O2 and depends on : external respiration
What is external respiration ?
Movement of gases between the air and the cells via both respiratory and cardiovascular systems
What is the pulmonary circulation ?
Delivers CO2 to lungs
Collects O2 from lungs
What kind of blood does the pulmonary artery carry and where does it travel ?
Carries deoxygenated blood away from the heart
only artery that carries deoxygenated blood
What kind of blood does the pulmonary vein carry and where does it travel ?
Carries oxygenated blood to the heart
only vein that carries oxygenated blood
What is the systemic circulation ?
Delivers O2 to peripheral tissues
Collects CO2 as waste
What change occurs between the respiratory and cardiovascular systems when energy demand is increased by working muscles ?
Respiratory- increased rate and depth of breathing
speeds up: substrate (O2) acquisition
waste disposal (CO2)
cardiovascular- increased heart rate and force of contraction
speeds up: substrate delivery to muscle via blood
waste removal via blood
What is the movement of O2 during gas exchange ?
O2 moves from inspired air to blood at the lungs
O2 moves from blood to cells at systemic capillaries
What is the movement of CO2 during gas exchange ?
CO2 moves from blood to air which is expired at lungs
CO2 moves from cells to blood at systemic capillaries
What is the relationship to the Net volume of gas exchanged in lungs per unit time and the Net volume exchanged in the tissues ?
Equal
what is the net volume of gas exchanged in the lungs ?
O2- 250ml/min
CO2- 200ml/min
What is the purpose of having equal volumes of gas exchanged between the lungs and tissues ?
Prevent gas build up in the circulation which would hamper has exchnage and helps to ensure that supply = demand
What is normal respiratory rate ?
12-18 breaths/min at rest
can reach 40-45 at max. when exercising
What is the function of the nose ?
Where air enters, cilia and mucus traps particles and warms and moistens the air
What is the pharynx ?
Air moves down into pharynx or throat
shared with digestive system
What is the Epiglottis ?
Small flap of tissue that folds over the trachea and prevents food from entering when swallowing
What is the larynx ?
Contains the vocal chords
Vibrates to produce sound
What is the function of the trachea ?
Moves air from the pharynx towards the lungs
What is the trachea composed of ?
Rings of cartilage to support and protect the trachea
What is the bronchus ?
Where air moves from the trachea then bifurcates (sternal angle) into left and right bronchi, which lead into the lungs
What are lungs ?
Main organ of respiration
soft and spongy texture due to hollow sacs
How many lobes does the right lung have ?
3
How many lobes does the left lung have ?
2
What fissure divides the superior and middle lobes of the right lung ?
Horizontal fissure
What fissure divides the middle and inferior lobes of the right lung ?
Oblique fissure
What fissure divides the superior and inferior lobes of the left lung ?
Oblique fissure
What are the components of the upper respiratory system ?
Nose
Pharynx
Epiglottis
Larynx
What are the components of the lower respiratory system ?
Trachea
Left and right main bronchus
Left and right lungs
Diaphragm
Where do the lungs sit ?
Pleural cavity
How many times does each bronchus branch ?
22 times, then terminating into a cluster of alveoli
Which primary bronchi is wider ?
Right
What maintains patency (open) of airways ?
C- shaped rings of cartilage
What doesn’t contain cartilage ?
Bronchioles
How is patency of bronchioles maintained ?
By physical forces in the thorax
What happens to diameter as we go down the respiratory tree ?
Diameter decreases
Where is there the greatest resistance to airflow in the respiratory tree ?
Conducting zone
(trachea, primary bronchi, smaller bronchi)
contains more molecules
branching increases surface area
Where does air in the conducting zone sit ?
Dead space
can’t participate in gas exchange
What can alter airway diameter and therefore resistance to air flow ?
Activity of bronchiole smooth muscle
What is the effect of contraction and relaxation on resistance ?
contraction- decreases diameter = increases resistance
relaxation- increases diameter = decreases resistance
What are the function of alveoli ?
Gas exchange
what surround each cluster of alveoli ?
Network of capillaries- allows gas exchange between respiratory and cardiovascular systems
Elastic fibres- allow inflation during inspiration, release stretch energy during expiration
What are type I cells ?
Site of gas exchange
make up bulk of wall
always adjacent to capillaries
What are type II cells ?
secrete surfactant
not involved in gas exchnage
lie adjacent to elastic fibres
What are alveolar macrophages ?
Sit between alveoli and ingest foreign material
What is the surface area of alveoli ?
80m2
very thin
Where is gas exchange only possible ?
Alveoli due to the very thin surface
The walls of the upper airways are too thick for gases to diffuse
What is the function of the upper airways ?
Conduction of air to and from alveoli (air in these airways is known as anatomical dead space as it can’t participate in gas exchange)
