The Respiratory System Flashcards
Why do we respire?
1) Take in oxygen
- drives aerobic cellular respiration
2) Remove carbon dioxide
Why do we need to remove carbon dioxide?
- prevents build up of this toxic waste product.
Other roles of Respiratory System?
- Temperature regulation
- Allows speech
- Acid base balance
- Water balance
Even some multicellular organisms are small enough to obtain their O2 by…
…diffusion
Small multicellular organisms which are small enough to obtain their O2 by diffusion tend to be…
…simple animals with flattened or tubular shapes to maximise surface area.
Such as:
- Flatworm
- Planaria
Oxygen diffuses…
…slowly
Because oxygen diffuses slowly, bigger animals including humans cannot…
…obtain oxygen only by diffusion
Larger animals have also evolved …
…transport systems, normally through circulatory systems
Different animals have respiratory systems that differ in:
structure
complexity
What systems have larger animals developed to carry out respiration?
- Tracheal systems
- Gills
- Lungs
Tracheal systems mainly seen in…
…insects
Gills seen in…
- many invertebrates
- fish
- some amphibians
Primitive lungs & book lungs found in…
- some snails
- spiders
Lungs seen in…
- some amphibians
- reptiles and birds
- mammals, including humans
The respiratory systems (RS) of other animals are often not as …
…efficient as ours
eg - the lungs of frogs
- This places limitations on the performance of other animals compared to mammals
avian lungs are more…
…efficient than ours
Getting O2 to cells can be divided into four main stages:
1) Ventilation
2) Gaseous exchange
3) Transport of gases
4) Entry into/exit from cells
What is ventilation?
the movement of air from the external environment to the respiratory surfaces
What is Gaseous exchange?
the diffusion of O2 and CO2 across the respiratory epithelium into the blood circulatory system
What is Transport of gases?
movement of gas from/to the lungs to/from the tissues (via the heart in humans)
What is entry into/exit from cells?
the diffusion of O2 and CO2 across the cell membrane for cellular resp.
Our Ventilation System is divided into…
…2 main regions
The two main regions of the ventilation system:
Upper and lower respiratory tract.
Whats the Upper Respiratory Tract?
airways of the head and neck, which include the nose, nasal cavity, pharynx (throat) and associated structures
Whats the Lower respiratory tract?
airways supplying the lungs and lung tissue, which include the larynx (voice box), trachea (windpipe), bronchi and lungs
Functionally, the respiratory system also consists of …
…two zones
Two zones of the respiratory system?
1) The Conducting Zone
2) The Respiratory Zone
What is The Conducting Zone?
consists of a series of interconnecting cavities and tubes outside and within the lungs
What is The Respiratory Zone?
consists of tubes and tissues within the lungs where gaseous exchange occurs
The conducting zone includes the…
…nose, nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles and terminal bronchioles
THe respiratory zone consists of…
…the respiratory bronchioles, alveolar ducts, alveolar sacs and alveoli
Function of The Conducting Zone?
function is to filter, warm, and moisten air to the lungs
Function of The Respiratory Zone?
- Main sites of gas exchange
- specifically the removal of carbon dioxide from, and the addition of oxygen to, the blood
Upper Respiratory Tract consists of…
Consists of nose, nasal cavity, pharynx & assoc. structures
Whats the nose?
Specialised organ
WHats the visible part of the nose called?
external nose
The nose is a supporting frame of…
- Bone and hyaline cartilage
- Covered with muscle and skin
- Lined by mucous membrane
Hyaline - somewhat…
…flexible (allows flexibility of the nose)
On the undersurface of the external nose are …
…2 openings
On the undersurface of the external nose are two openings called …
…external nares or nostrils.
Nasal vestibules in the nose are lined with …
…coarse hairs
On the undersurface of the external nose are two openings called external nares or nostrils. These openings lead to …
… cavities called nasal cavities.
Nasal vestibules lined with coarse hairs – why?
Filter out large dust particles from inhaled air
In fact, the interior structures of the nose have three functions:
1) warming, moistening and filtering incoming air
2) Detecting olfactory stimuli
3) Modifying speech vibration (hollow resonating chambers)
Whats the internal portion of the nose called?
nasal cavity (internal nose)
The nose is divided into…
right and left sides by:
the nasal septum
What are Nasal Cavity and Sinuses
Ducts from the paranasal sinuses and nasolacrimal ducts
Function of paranasal sinuses and nasolacrimal ducts?
1) also open into nasal cavity
2) paranasal sinuses drain mucous and nasolacrimal ducts drain tears.
Sinuses are …
…air-filled spaces within the bones of the skull
Sinuses connect to…
…the nasal cavity
The sinus reduce…
…skulls relative weight
Sinuses act as
resonating chambers for sound as we speak / sing
Nasal cavity (NC) divided into:
- larger, inferior respiratory region
- smaller, superior olfactory region
the larger, inferior respiratory region is lined with…
…ciliated columnar epithelium with numerous goblet cells
the larger, inferior respiratory region is often called …
…the respiratory epithelium
the smaller, superior olfactory region is responsible for…
…smelling
Nasal Conchae extends out of…
…lateral wall of Nasal cavity
The nasal conchae has…
three shelves formed by projections of the:
- superior nasal conchae
- middle nasal conchae
- inferior nasal conchae
The nasal conchae subdivide…
…each side of the nasal cavity (NC)
- groove-like air passages
- meastuses