Tissues in the lungs - Structure
- Created by: Steff06
- Created on: 11-04-16 11:39
View mindmap
- Tissues in the lungs:
- Trachea, bronchi and bronchioles are airways that allow passage of air into the lungs and out again.
- To be effective, the airways must:
- Larger airways must be large enough to allow sufficient air to flow without obstruction.
- Must DIVIDE into smaller airways to deliver air to all the alveoli.
- Airways must be STRONG enough to prevent them from collapsing when air pressure inside is low during inhalation.
- Must be FLEXIBLE to allow movement.
- Must be able to STRETCH and RECOIL.
- Trachea and bronchi:
- Have a similar structure. Only differ in SIZE. Bronchi are NARROWER than the trachea.
- Both have relatively THICK WALLS that have several layers of tissue.
- Much of the wall consists of CARTILAGE.
- Cartilage is in the form of INCOMPLETE RINGS/C-rings in the TRACHEA, but is LESS REGULAR in the bronchi.
- On inside surface of cartilage is a layer of GLANDULAR TISSUE, CONNECTIVE tissue, ELASTIC FIBRES, SMOOTH MUSCLE and BLOOD VESSELS. Often called the LOOSE TISSUE.
- Inner lining is an EPITHELIUM layer that has 2 types of cell. Most cells have CILIA known as CILIATED EPITHELIUM. Among these ciliated cells are GOBLET CELLS.
- Bronchioles:
- Bronchioles are much NARROWER than the bronchi.
- Larger bronchioles may have some CARTILAGE, but smaller ones have NO cartilage.
- Wall is mostly made of SMOOTH MUSCLE and ELASTIC FIBRES.
- Smallest bronchioles have CLUSTERS of ALVEOLI at their ends.
Comments
No comments have yet been made