Introduction and anatomy of lungs, airways and blood supply Flashcards
What are the four functions of the respiratory system
Gas exchange – Oxygen added to the blood from the air, carbon dioxide removed from the blood into the air.
Acid base balance – regulation of body pH
Protection from infection
Communication via speech
What is the pH of the acid base balance maintained by the respiratory system
pH 7.4
What mechanism of the nose protects you from infection
Its in contact with the external environment, and is lined with lymphoid tissue which scan particles coming in
Mucous production traps particles
Cila present
What is cilla
pseustratified columnar epithelium
How does the respiratory system allow communication
When expiring the air over vocal chords causes vibration which are then refined to make words
What is the significance of gas exchange
The oxygen gained allows ATP generation
removes CO2 as the waste product
For external respiration to occur what is needed?
The integration of the cardiovascular system with the respiratory system
What is the name of the two circulation involved in external respiration
Pulmonary circulation
Systemic circulation
What is the purpose of the systemic circulation and where does it take place?
Takes place in the capillaries, picking CO2 up from the blood and taking it to the lungs, while delivering oxygen to the blood
What is the pulmonary circulation rich in
CO2
What is the purpose of the pulmonary circulation
Deliver CO2 to the lungs from the blood and pick up oxygen from the lungs and take it to the heart
What takes the deoxygenated blood away from the heart and why is this so unusual
Pulmonary artery
Only artery in the body to cary deoxygenated blood
What takes the oxygenated blood to the heart
pulmonary vien
Where does pulmonary circulation in the respiratory tract occur and why there?
The alveoli, due to the thinnest of the walls
What affect does exercise have on the circulation and what does this result in?
An increase in the rate and depth of breathing speeds
Heart rate and force contraction speed up
A greater volume of oxygen being delivered quickly
Define steady state
net volume of oxygen exchanged in lungs per unit of time equal to volume exchanged in the tissues
What is the average breathing rate
10-20 breaths per minute
Why is it important to maintain gas levels
For blood concentrations
What is present in the upper respiratory tract and what is its purpose
nasal cavity pharynx epiglotis Layrnx CONDUCTING SYSTEM
What is present in the lower respiratory tract and what is its purpose
Trachea
Bronchus
Lungs
WHERE GAS EXCHANGE OCCURS
What part of the reparatory system is shared with the digestive system
pharynx
What prevents food molecules entering respiratory tract and where is it located
epiglotis folds over trachea
What points upwards and contains your vocal chords
Larynx
Why is the nose more effective than the mouth for breathing
Is more comfortable as the noise moistens and warms the air
What has less air resistance the mouth or the nose
The mouth
What lines the respiratory tract
Epithelium Glands Lymph nodes Blood vessels Cilla Mucous
What is the purpose of mucous
Moistens air
Traps particles
Provides large surface for cilla to act on
What cells is mucous produced from and what type of cells are they?
Goblet cells - subepithelial glands
**Where does the alveoli receive its blood supply from
pulmonary artery
What feature of the alveoli allows efficient gas exchange
thin membrane
What cells are present in the alveoli
Type 1 pneumocytes
Type 2 pnuemocytes
Macrophages
What is the function of Type 1 pneumocytes and what type of cells are they
Gas exchange
simple squamous epithelium
What is the function of Type 2 pnuemocytes
Reduce the work of breathing by reducing surface tension at alveolar surface by the production of surfactant
Is elastic fibres present in the alveoli
Yes
Is smooth muscle present in the alveoli
No
Where does air move from the trachea
to the left and right bronchus inside the lung
Where does the bronchi terminate
at the alveoli
What are the steps in the progression of the bronchi branch
epithelium becomes more squamous
The diameter decreases
Mucous cells decrease - absent in the alveoli
Cilla cells decrease - absent in the alveoli (last thing to disappear)
What happens to the resistance in the bronchi branch progresses to the alveoli?
upper respiratory has a wider diameter but even though the diameter decreases there is more pathways available for the gas, therefore less gas particles per route, decreasing the resistance
What effect does contracting smooth muscle have on the respiratory tract
decreases diameter therefore increases resistance
What is it called when the trachea splits into the two bronchi
Bifurcation
What is different about the right branching to the left branching of the bronchus
Right bronchus is larger and greater in width
The right bronchus also follows on to further branch into 3 bronchi compared to the left which branches into a further 2
What bronchi are foreign bodies more likely to be trapped into
Right
Typical values of gas exchanged at the lungs are:
250ml Oxygen and 200ml Carbon dioxide per minute
The first airways to lose their cartilaginous rings are the
Upper bronchioles
