Respiratory - The lung 1/2 Flashcards
What is the function of the lungs?
Internal pockets of the body surface which allow atmospheric air to be brought close to the pulmonary capillaries so gas exchange can occur
What are the two things necessary for efficient exchange?
Diffusion distance between air and blood must be small
The surface area for gas exchange most be large
What is the diffusion distance inside the lungs?
0.5 micrometers (1/50 of the diameter of a red blood cell)
What is the internal surface are of the lungs?
100ms2
What is external respiration?
The process by which oxygen is absorbed from the atmosphere into the pulmonary capillaries and CO2 is excreted (i.e. from outside to inside body)
What is internal respiration?
The exchange of gases between blood in systemic capillaries and the tissue fluid and cells which surround them (i.e. from blood to cells)
What is cellular respiration?
The process within individual cells where they gain energy by breaking down molecules such as glucose
What is pulmonary ventilation?
The bulk movement of air into and out of the lungs
What is the conduction part of the respiratory system?
Series of cavities and thick wall tubes which conduct air between eh noes the the deepest parts of the lungs
What is the function of the conduction part of the respiratory system?
Warms, humidifies and cleans the air (no gas exchange FYI)
What makes up the conduction system?
Nasal cavities, pharynx, larynx, trachea, bronchi and bronchioles (i.e. the tubes)
What is the respiratory part of the respiratory system?
Comprising the tiny thin walled airways where gases are exchanged between air and blood
What makes up the respiratory part?
Bronchioles, alveolar duct and sac and alveoli (i.e. the end of the tubes)
What are the three stages of respiration?
External respiration (air –> blood), internal respiration (blood –> tissue) and cellular respiration (tissue – > energy)
What is the difference between respiration and ventilation?
Ventilation is the mechanical movement of air in and out of the lungs, respiration is the movement of gases through the body
What are the two parts of the respiratory tract?
Upper and lower respiratory tract
What structures make up the upper and lower respiratory tract?
Upper = Nasal cavity – > larynx
Lower = Trachea –> alveoli
How does an illness in the upper vs lower respiratory tract differ?
Illnesses in the upper respiratory tract are normally viral and can remedy themselves or with antibiotics, lower respiratory tract is more serious and is likely to lead to more serious conditions such an pneumonia
In the conduction part of the respiratory system, what needs to happen to the air?
The air needs to be warmed to 37ºC, removes pathogens and particle from the air and humidify the air to 100%
What is the function of the nasal cavity?
Begins the process of humidifying an dwarfing the air and it slows the air down
Label the diagram
Label the diagram
What is the function of the conchae?
It increases the surface area of the nasal cavity to help mix/slow down the air
What is the whole nasal cavity covered in?
Mucus membrane
What is the purpose of the mucus membrane?
Produces a sticky layer that is able to clean the air
What is the mucus membrane made of?
Ciliated epithelium and goblet cells
What do the goblet cells do?
They produce the mucus layer
What is the state of the epithelium?
It is motile (i.e. it is beating)
What is the process of the filtering the air with the mucus membrane called? What does it do?
It is called the muco-cillary escalator and it transports the filtered substances into the stomach
What is underneath the ciliated epithelium? What does this do?
Rich blood supply from a capillary network = Causes warming of the air (blood is 37ºC FYI)
Serous/Mucous glands = Humidifies the air as it produces a watery secretion
What does the roof of the cavity have? What do they do?
Olfactory epithelium which detects smell
Label the diagram
What goes down each of the pipe in the pharynx?
Nasopharynx = air
Oropharynx = food
Laryngopharynx = air and food
What is the oesophagus made of?
Elastic cartilage
During swallowing, what happens to the pharynx to prevent choking?
The soft palate (tissue separating nasal cavity and mouth) closes the nasopharynx and the epiglottis closes and becomes a glottis preventing food form going down the trachea
What is the epiglottis called when it is closed?
Glottis
How many lobes of the lungs are there in the left and the right?
3 in the right, 2 in the left
Why are there less lobes in the left lung?
Needs space for the heart
What is the name of the windpipe?
Trachea
What keeps the trachea open?
C-chaped cartilage rings
Why are the rings of the trachea C-shaped?
So that the the trachea is maintained opened but there is still some flexibility
What is the trachea lined with?
Ciliated epithelium and mucous glands to transport mucous sheet to the nasopharynx
Label the diagram, what is it showing?
Shows the Bronchus wall
What is the purpose of the smooth muscle in the bronchus?
They don’t really have one (the cartilage keeps the air way open)
What are the two source of mucus in the bronchus? Why?
Goblet cells and mucus glands
There needs to be a lot of ciliated cells on top so that the mucus can be moved so there isn’t much room for goblet cells therefore mucus glands
There are alveoli in the wall of the bronchus, why?
To increase the overall surface are of the lungs for gas exchange, alveoli occupy any space they can
Label the diagram, what is being shown?
The wall of the bronchiole
What is the purpose of the club cells?
They produce a water secretion to prevent the drying out of the epithelium
What are some of the differences between the wall of the bronchus and the bronchiole? Why?
- Bronchiole is much thinner: the pathway into the lower respiratory tract becomes smaller so thinner branches are needed
- There are no goblet or mucus glands, only club cells: by the point of the bronchiole (i.e. generation ~15) the air should be clean, humid and warm enough so it is just about maintain it with
