6 Lungs

Explain the need for specialised exchange surfaces, to include surface area to volume ratio (SA:V), metabolic activity, single-celled and multicellular organisms.

Describe the structures and functions of the components of the mammalian gaseous exchange system:

cartilage

ciliated epithelium

goblet cells

smooth muscle

Elastic fibres

Describe the mechanism of ventilation in mammals, to include the function of the rib cage, intercostal muscles (internal and external) and diaphragm.

Describe and explain the features of an efficient exchange surface

Describe and explain the relationship between vital capacity, tidal volume, breathing rate and oxygen uptake, and analyse and interpret primary and secondary data e.g. from a data logger or spirometer.

Describe the mechanisms of ventilation and gas exchange in bony fish and insects.

Explain how to carry out the dissection, examination and drawing of the gaseous exchange system of a bony fish and/or insect trachea

increased surface area

root hair cells,

thin layer

– alveoli,

good blood supply/ventilation

– gills