AS Biology F211 Membranes and Transport

AS Biology F211 Membranes and Transport. 

HideShow resource information
  • Created by: Pheebie
  • Created on: 15-10-11 15:19

Characteristics of an Exchange Membrane

  • Thin exchange membrane, so its easy for particles to get through.
  • Large Surface area so lots can get through at once.
  • Moist surface for particles to dissolve into so they can pass through.
  • Permeable wall for particles to get through.
  • Good blood supply to maintain concentration gradient.
1 of 7


Function:- Hold tubes up and open to allow air to flow through. Allow increase and decrease in air pressure.

Distribution:- Bronchi and Trachea support.



2 of 7

Ciliated Epithelial Cells

Function:- Cilia on cells sweeps mucus up to the back of the throat.

Distribution:- Inside of the trachea.



3 of 7

Goblet Cells

Function:- Secretes mucus. Forms a protective layer over epithelium preventing cells from drying out.

Distribution:- Trachea Wall.



4 of 7

Smooth Muscle

Function:- Contracts and relaxes to widen trachea when doing exercise. Involuntary muscle.

Distribution:- Walls of trachea, bronchi and bronchioles.



5 of 7

Elastic Fibres

Function:- Help decrease volume in lungs by coiling back into shape after they were stretched. 

Distribution:- In the alveoli. 



6 of 7


Vital Capacity:- Maximum volume of air that can be breathed out after breathing in as deeply as possible.

 Tidal Volume:- Volume of air breathed in or out during a single breath.

Breathing rate:- Mean number of breaths per minute.

Ventilation rate:- Volume of air moved into and out of the lungs per minute.

Expiratory reserve volume:- The maximum volume of air over and above the tidal volume, that can be breathed out.

Inspiratory reserve volume:- The maximum volume of air over and above the tidal volume that can be breathed in.

7 of 7


No comments have yet been made

Similar Biology resources:

See all Biology resources »