Exchange Surfaces Flashcards
What features of exchange surfaces allow for fast and efficient exchanges?
Large surface area
Short diffusion distance
Maintain concentration gradient
Moist
What do goblet cells secrete?
Mucus, Goblet cells trap dust and microorganisms to prevent infection.
Where are goblet cells found?
Trachea, bronchi, and larger bronchioles These cells are integral to the respiratory system.
These cells are integral to the respiratory system.
What is the function of cilia in the respiratory system?
Move mucus up towards the throat
This helps in swallowing and destroying mucus by stomach acid.
Where are cilia located?
Trachea, bronchi, and bronchioles
Cilia are important for maintaining airway hygiene.
What do elastic fibres do during breathing?
Stretch when we breathe in and recoil when we breathe out
This function aids in efficient gas exchange.
Where are elastic fibres found?
Walls of the trachea, bronchi, bronchioles, and alveoli
Elastic fibres contribute to the elasticity of the respiratory structures.
What is the role of smooth muscle in the airways?
Control and relax to expand or narrow the airways
This regulation is crucial for airflow and resistance.
Where is smooth muscle located in the respiratory system?
Trachea, bronchi, and bronchioles
Smooth muscle plays a key role in airway responsiveness.
What is the function of cartilage in the trachea and bronchi?
Provides support and prevents the airways from collapsing
Cartilage maintains airway patency during inhalation.
How is cartilage structured in the trachea and bronchi?
Found in rings
The ring structure provides both strength and flexibility.
What is the structure of the lungs
Each of the lungs is enclosed in a double membrane known
as the pleural membrane. The space between the two
membranes is called the pleural cavity, and is filled with small amount of pleural fluid.
What are the Key Structures of the Nasal Cavity
Large surface area and good blood supply – this
warms the air as it passes into the body
Hairy lining – hairs trap dust and bacteria in
mucus and prevent them from reaching the lungs,
which could cause infection
Moist Surfaces – increases the humidity of the
incoming air, this reduces the evaporation of
water in the lungs
What are the Key Structural components of the Trachea
This pipe is supported by a
layer of cartilage that holds the trachea open and prevents it from collapsing
The rings are incomplete to allow it the bend when food is swallowed down the esophagus behind
The trachea is lined with ciliated epithelial (push mucus) and goblet cells (create mucus) that prevent dust and bacteria from entering
What are the Key Structural components of the Bronchus
The bronchus are extensions of the trachea that split into two for the left and right lung
This has a very similar structure to the trachea but smaller
Cartilage rings hold the pip open
What are the Key Structural components of the Bronchioles
The bronchus split into much smaller bronchioles
This are about 1mm or less in diameter
They have not cartilage and are held open by smooth muscle
When this muscle contracts the bronchioles contract, this dependent on air flow
They are lined with a thin layer on epithelial tissues making some gas exchange possible
What are the Key Structural components of the alveoli?
The alveoli are little air sacs, this is where most of the gas exchange occurs
Each alveoli is about 200 -
300μm in diameter
They are made up of a thin
layer of flattened epithelial
cells, as well as some
collagen and elastic fibres
The elastic fibres causes
recoil which helps move air
out of the alveoli
What is Inspiration/inhalation , and what are the steps/features within the process
Inspiration
This is an energy using (active) process:
Diaphragm – Moves Down
Intercostal Muscles – move up and out
Thoracic Volume – Increases
Thoracic Pressure – Decreases
Air Flow – In to lungs (to equalise the pressure
difference)
What is Expiration/exhalation , and what are the steps/features within the process
This is a largely passive process:
Diaphragm – Moves up
Intercostal Muscles – move down and in
Thoracic Volume – decreases
Thoracic Pressure – increases
Air Flow – out the lungs (to equalise the pressure
difference)
In inspiration what muscles move?
Contraction of the external intercostal muscles.
In expiration what muscles move?
Contraction of the internal intercostal muscles
mechanics of inspiration (3 marks)
Inspiration:
External intercostal muscles
contract, lifting rib cage
Diaphragm muscles contract,
pulling it downwards
Volume of lungs increase
Pressure inside the lungs
decreases
Air rushes into the lungs from
the trachea to attain a pressure
equilibrium
mechanics of expiration (3 marks)
internal intercostal muscles
contraction, rib cage falls
Diaphragm muscles relax and
it moves
upwards
Volume of lungs decreases
Pressure inside the lungs
increases
Air rushes out of the lungs to
attain a pressure equilibrium
How does the spirometer work?
Static lower half of tank is
full of water, Mobile upper half of tank is full of oxygen, Breathe out into the tank, and the upper half will rise, Breathe in from the tank and the upper half will fall, Trace marker is attached to the mobile upper half
What is a peak flow meter?
A peak flow meter
measures the rate at
which air can be expelled
from the lungs
Why does the overall volume of gas
in the tank decline over time?
The spirometer contains Soda lime which absorbs carbon dioxide, When breathing, we are using up
the oxygen from the tank, while the carbon dioxide we breathe out is absorbed by the soda lime As a result the gas volume of tank decreases over experiment, Decreases by volume of oxygen used up by the participant
What is tidal volume?
The volume of air that moves into and out of the
lungs with each resting breath
What is Vital capacity?
The largest volume
of air that can be
breathed in
What is Inspiratory Reserve Volume?
The maximum volume of air you can breath in over
and above normal inhalation
What is Expiratory Reserve Volume?
Maximum volume of air you can force out of your
lungs over and above the normal tidal volume of air
you breath out
What is Residual Volume?
The volume of air that is left in your lungs when you have exhaled as hard as possible
What is Total Lung Capacity?
The sum of the vital capacity and the residual volume
