B11 - Gas Exchange in humans Flashcards
What do lungs provide? [1]
A gas exchange surface
What are the lungs protected by? [1]
The ribcage
Where in the lungs does gas exchange happen? [1]
Alveoli
What is the ribcage made up of? [2]
- Ribs (bone)
- Intercostal muscles
What is the voice box called? [1]
Larynx
What is the function of the LARYNX? [2]
Air passes through here during breathing; vocal cords are found here.
What is the windpipe called? [1]
Trachea
What is the function of the TRACHEA? [2]
Tube carrying air to and from the lungs.
Why are there C shaped rings of cartilage around the trachea? [2]
To prevent the trachea from collapsing.
What is the function of alveolus/alveoli? [2]
It is where gas exchange takes place; surrounded by capillaries.
What are capillaries? [2]
Delicate blood vessels that exist throughout our bodies. They transport blood, oxygen and nutrients to cells in your organs and body systems.
What is the function of the bronchiole? [2]
They are small tubes transporting air between the bronchi and the alveoli.
What is the function of the diaphragm? [2]
It is a sheet of muscle below the ribcage involved in breathing/ventilation.
What is the function of the lungs? [2]
They are large structures that provide the gas exchange surface.
What is the function of the bronchi/bronchus? [2]
They are 2 smaller tubes transporting air between the trachea to the bronchioles.
What is the purpose of lungs? [1]
To breathe
Why do we need to breathe? [2]
To get oxygen in your body and carbon dioxide out.
How do all of our cells get the energy they need to function? [1]
Cellular Respiration
To carry out cellular respiration, what do you need? [1]
Oxygen
What is the role of the lungs? [2]
To get oxygen that we need from the air all around us, into our bloodstream - where it can be transported to the rest of our body.
What is a similarity between an alveolus and the blood capillaries right next to it? [2]
They both are made up of just one layer of very thin cells.
What does one layer of thin cells increase? [2]
It increases the rate at which carbon dioxide and oxygen can diffuse across.
How do alveoli have a very large surface area? [2]
- Adults have hundreds of millions of alveoli
- If all the alveoli were spread out flat - they would cover half a tennis court.
Alveoli walls are ….. . What does this allow and what does this increase? [3]
- Moist
- Allows gases to dissolve
- Increases the rate of diffusion
What is CO2 being carried by? [1]
The plasma
What 5 things make alveoli good for gas exchange? [5]
- Large Surface Area
- Very thin
- Moist Lining
- Good supply of blood
- Good ventilation
How do alveoli have a good supply of blood? [2]
Each one of the alveoli has lots and lots of capillaries surrounding it.
How do alveoli have good ventilation? [2]
This means good supply of air which is supplied by breathing.
Where are oxygen and carbon dioxide exchanged? [2]
- The lungs
- The tissues of the body
In which direction does the oxygen exchange happen? [2]
Air in lungs –> blood –> tissues
In which direction does the carbon dioxide exchange happen? [2]
Tissues –> blood –> air in lungs
How do gases move across the wall of the alveolus? [1]
Diffusion
What is diffusion? [3]
Diffusion is the net movement of particles from an area of higher concentration to an area of lower concentration as a result of random movement until an equilibrium is reached.
What are 3 ways diffusion happens quickly? [3]
- Short distance
- Large surface area
- Steep concentration gradient
What is limewater used for?
Testing of carbon dioxide.
What happens to limewater if there is carbon dioxide present? [2]
The limewater turns cloudy/milky.
Exhaled air contains (3 things) than inhaled air. [3]
- less oxygen
- more carbon dioxide
- a little more water vapour
