Breathing and respiratory system Flashcards
Diaphragm
sheet of muscles that aid breathing, diaphragm muscles contract and relax moving diaphragm up and down
Intercostal muscles
muscles between ribs that aid breathing, contract and relax moving ribs up and out and down and in.
Alveoli
small air sacs where gas exchange takes place.
Bronchus
Branches trachea to bring air into lungs. Also supported by rings of cartilage. Connects Trachea to the bronchioles
Trachea
Brings air into lungs, tube that runs down from mouth to throat towards lungs
Bronchioles
connects bronchus to the alveoli, branches off bronchi.
Ribs
Protects internal organs of the thorax, moves up and down which inflate and deflate lungs.
Pleural membranes
Thin layers that reduce friction between lungs and inside of chest wall during breathing.
Pleural fluid
fluid found in pleural cavity{ between pleural membrane layers} reduces friction during breathing
Inhalation
Intercostal muscles contact moving ribs up and out
Diaphragm contracts moving downwards
The volume of chest cavity {thorax}increases causing pressure to decrease
Air enters the lungs because the thorax pressure falls below atmospheric pressure
Exhalation
intercostal muscles relax causing the ribs to move down and in
Diaphragm relaxes and returns to its original dome shape
The volume of the thorax decreases raising pressure inside the thorax which forces air out of the lungs
How does the lung model show inhalation
when diaphragm( rubber sheet) is pulled down the volume in the glass jar increases(thorax)
This increases volume causing pressure to decrease
The lungs(balloons) inflate as air enters until pressure inside and out are equal
lung model shows exhalation
when the diaphragm (rubber sheet) is released the volume inside the thorax decreases
this decrease in volume causes pressure to increase
The lungs(balloons) deflate as air exits until pressure inside and outside are equal
Faults
ribs and intercostal muscles are not represented
the ribs can move in and out, the sides of glass jar cannot move
in humans there is a limited space between the lungs and the chest wall but the model shows a large space between chest bell jar and lungs
In humans diaphragm is usually dome shaped
Effect of exercise on breathing rate and depth
muscle cells require more energy during exercise, energy is made during exercise/respiration
when exercising, cells will need more 0xygen and produce more carbon dioxide
when blood reaches lungs, a larger volume of air is needed to replace the oxygen needed and remove the carbon dioxide produced by this extra respiration
The time taken for breathing rate to return to normal is called recovery time.
Breathing rate
number of breaths per minute
depth of breathing
volume of air per breath
What happens at the alveoli
At the alveoli, oxygen passes from lungs into blood so that it can be carried around the rest of the body
Carbon dioxide is produced by the body cells during respiration. It is carried by the blood from the body cells to capillaries surrounding the alveoli, here the carbon dioxide passes from the blood to the alveoli
therefore oxygen from lungs is being exchanged for carbon dioxide from blood.
Respiratory surface
the parts of living organisms across which respiratory gases can be exchanged between the environment and the organisms cells
Large surface area
millions of alveoli increase the surface area and allows more gas to diffuse across it at the same time
moisture
the gases must dissolve in water/moisture before diffusion will occur. It will prevent cells from drying out and dying.
Good blood supply
the alveoli must be in contact with many blood capillaries to ensure that any oxygen that passes into blood is quickly carried away. Blood supply ensures carbon dioxide is carried quickly towards the alveoli
Extremely thin and permeable
one cell thick, Gases diffuse quickly across this barrier due to short diffusion distance between the two layers of cells.
Steep diffusion gradient
if concentration of oxygen in alveoli is high and concentration in blood is low then diffusion will occur rapidly
Animals maintain a high concentration of
oxygen in alveoli by breathing in.
to ensure rapid diffusion of carbon dioxide from capillaries to alveoli then a high concentration of carbon dioxide must be present in the blood and a low concentration must be maintained in the alveoli.
