Exchange Surfaces Flashcards
What are the lungs?
They are a pair of structures that have a large surface area that is located in the chest cavity with the ability to inflate.
What surrounds the lungs?
The rib cage - protects them.
What is lubricating substance for the lungs ?
Prevent the friction between the ribcage and the lungs
What contracts, raises and lowers the ribs?
External and intercostal muscles
What’s does the diaphragm do?
Separates the lungs from the abdominal area
Where does gaseous exchange occur
Alveoli
What animal have a bigger or smaller SA:V ratio
Smaller organisms
What are the special exchange features of a Root hair cell?
- Grow into long hairs that stick out into the soil.
- each plant will be covered in millions of these microscopic hairs
- gives a roots a high surface area for the osmosis of water and mineral ions by active transport
What are the special features of exchange surfaces?
Good blood supply
Large surface area
thin
Describe the process of inhaling and exhaling
Inhale:
- the external intercostal muscles and diaphragm muscles contact
-this causes the rib cage to move upwards and outwards and the diaphram to flatten to increase the volume
-as the lung volume increases, the pressure decreases allowing air to flow into the lungs.
Active process.
Exhale:
-External intercostal and diaphragm muscles relax
-moving the ribcage to more downwards and inwards and the diaphragm to curve again.
The chests volume decreases and the pressure increases so air is forces out of the lungs.
Passive process - No energy when breathing normally.
What happens the expiration os forced
The internal intercostal muscles contract and pull the ribcage down and in.
What are goblet cells?
Line the airways and secrete mucus
What is the function of Cilla?
To move mucus and other trapped microorganisms away from the alveoli towards the throat were swallowed. prevent lung infections.
What are elastic fibres for?
Help the process of breathing out.
They are found on the wall of trachea bronchi and bronchioles. when breathing in, the lungs inflate and the elastic fibres are stretched then recoiled to push there air out
What are the rings of cartilage for?
provide support for the trachea and bronchi. Strong but flexible, stops from collapsing when you breath in and pressure drops.
