Introduction and Anatomy of Lungs, Airways and Blood Supply Flashcards
What are some functions of the respiratory system?
Gas exchange
Acid base balance
Protection from infection
Communication via speech
What is the gas exchange that takes place?
Oxygen added to the blood from the air
Carbon dioxide removed from the blood into the air
How does speech occur?
Larynx vibrating and manipulating air
Does speech occur on inspiration or expiration?
Expiration
In basic terms, why do we breathe?
We need oxygen for energy, which fuels cells and allows them to perform their functions
What would being unable to breathe oxygen do to us?
Our cells would die, and then we would die
How can enery be produced without oxygen, and why is this not feasible long term?
Anaerobic respiration, but this does not produce enough energy
What is produced when oxygen is burned?
CO2 as waste
What is external respiration?
Oxygen going in and out of the body
What is internal/cellular respiration?
Biochemical process within cells
What vessel carries blood from the heart to the lungs and is this oxygenated?
Pulmonary artery which carries deoxygenated blood
What vessel carries blood from the lungs to the heart and is this oxygenated?
Pulmonary vein carries oxygenated blood from the lungs to the heart
What two systems does external respiration require integration of?
Respiratory and cardiovascular
What are the exchanges of oxygen present once we intake air?
1) Between atmosphere and lung (alveoli)
2) Between lungs and blood
3) Between the blood and cells (transported to cells in the blood)
What are alveoli?
Regions of the lung that are thin enough to allow gas exchange
What are arteries?
Vessels that carries blood away from the heart
What are veins?
Vessels that carries blood towards the heart
What are the two kinds of circulation relevent to the lungs?
Pulmonary circulation
Systemic circulation
How does pulmonary circulation and systemic cirulation contrast each other?
Pulmonary delivers CO2 and picks up oxygen
Systemic delivers O2 and picks up CO2
Which of the pulmonary vein and artery carries oxygenated blood?
Pulmonary vein
What displays the intimate relationship between the respiratory and cardiovasular systems during an increase in energy demand?
Rate and depth of breathing increase (more oxygen acquired and carbon dioxide diposed of)
Heart rate and force of contraction increases (delivered to muscle and waste removed quicker)
Why can gas exchange only take place in capillaries?
The walls are thin enough to allow it
Where are the 2 places that gas exchange occurs in the respiratory system?
Lungs (alveoli)
Systemic capillaries
What is oxygen and CO2 exchange like in steady state?
Net volume of oxygen and CO2 exchange in the lung per unit of time is equal to the net exchange at the tissue
What are the average volumes of O2 and CO2 exchanged per minute?
250ml of oxygen
200ml of CO2
What are the typical breathing rate of someone at rest and at maximum exercise?
10-20 breaths/min at rest
40-45 breaths/min at maximum exercise
What is A?
Pharynx
What is B?
Trachea
What is C?
Lung
What is D?
Bronchus
What is E?
Larynx
What is F?
Epiglottis
What is G?
Nose
What systems is the pharynx shared between?
Digestive and respiratory
What is the trachea made up of?
Stiff rings of cartilage that protect it
What does the epiglottis do?
Folds over the trachea and prevents food from entering it when you swallow
What is the larynx also known as?
Voice box
Why is the nose prefered for breathing over the mouth?
Large surface area allows it to be better at warming and moistening the air
What is everything in this diagram known as?
Conducting airways
What are conducting airways?
Ones that have thick walls and so no gas exchange takes place, they carry air to where gas exchange can take place
How does the structure of the bronchus change as it goes deeper into the lungs?
It continues branching until it becomes sacs (alveoli) where gas exchange can take place
What are the 2 things the respiratory system can be divided into?
Upper and lower respiratory system
Where does the upper respiratory system end?
Larynx and epiglottis (they are included)
Where does the lower respiratory system begin?
Trachea (included)
What is the diaphragm?
Large sheet of muscles that seperates the thoracic cavity from the abdominal cavity
What can the lung be seperated into?
Lobes
How many lobes does the left and right lung have?
Left lung has 2 lobes
Right lung has 3 lobes
What is each lobe seperated by?
Fissure
What are the 3 lobes in the right lung called?
Superior lobe
Middle lobe
Inferior lobe
What are the 2 lobes in the left lung called?
Superior lobe
Inferior lobe
What are the fissures present in the right lung called?
Horizontal fissure (seperates superior and middle lobes)
Oblique fissure (seperates middle and inferior lobes)
What are the lungs surrounded by which appears black in images?
Pleural cavity
What does the bronchi seperate into, and what does this seperate into, and what does this further seperate into?
Primary bronchi, which seperates in secondary bronchi that goes into each lobe, which seperates in tertiary bronchi that seperates into bronchi-pulmonary sections
What is different between the right primary bronchi and the left?
Width and angle
In which primary bronchi do most foreign bodies become lodged and why?
Right because of the more verticle angle and wider shape
What do bronchus become when cartilage stops?
Bronchiole
What is each stage in the branching of airways between the larynx and the alveoli?
Larynx - trachea - primary bronchus - secondary bronchus - tertiary bronchus - bronchiole - alveoli
How many levels of branching is there between the trachea and alveoli?
About 23
What is patency?
Airway is patent when it is open
What maintains patency in the trachea?
Cartilage
What maintains patency in the bronchioles?
Physical forces in the thorax
In which part of the airway does most resistance occur and why?
Upper airway, although they are wider than the lower because more air is competing for the space
How can airway diameter be altered?
Contracting bronchial smooth muscle
What does altering airway diameter in turn alter?
Airway resistance
What does contraction of the bronchial smooth muscle do?
Decreases airway diameter and so increases resistance
What does relaxation of the bronchial smooth muscle do?
Increases airway diameter and so decreases resistance
What is asthma?
Inappriopriate contraction of bronchial smooth muscle
What is each cluster of alveoli surrounded by?
Elastic fibres and a network of capillaries
What are the 2 types of cells that compose alveoli?
Type 1 (exchange gas with blood) Type 2 (synthesis surfactant)
What do elastic fibres do to alveoli?
Sits in interstitial space and seperates them
What ingests forign material that reaches the alveoli?
Alveoli macrophages
What is surfactant?
Substance that lowers the tension between two other substances
What is the air in upper airways termed as and why?
Anatomically dead because it cannot participate in gas exchange
What does each lung have a capacity of?
3L
What are some functions of mucous?
Moistens air
Traps particles
Provides large surfaces area for cilia to act on
What produces mucous?
Goblet cells
What does cilia line and what does it do?
Trachea where it beats mucous away from the lower respiratory tract
What do goblet cells and cilia terminate before, and which terminates first?
The level of the bronchia, with goblet cells terminating first
