The Old Guard

Stomatal Closure: The Old Guard Takes Up the SLAC

Flowering plant stomata close through passive dehydration or by active pumping of anions through SLAC, a phospho-activated membrane channel. A new study reports that moss likely utilise this same mechanism, and thus supports an early origin for SLAC-mediated active stomatal control.

The Old Guard takes up the SLAC: the evolution of active stomatal closure

Guard cells

What are guard cells? A pair of guard cells surrounds each stoma on the leaf surface. Stomata are important because they regulate the uptake of CO 2 from the atmosphere for photosynthesis and also the loss of water vapour from the plant during transpiration. The aperture of the stomatal pore is controlled by the two guard cells. When the guard cells are fully turgid the pore gapes open, whereas...

"On guard at the gateway".

TO the general public the work of the Port Health Service is little known with the result that it gets very little publicity except on those rare occasions when a large passenger liner is held up with a case of suspected smallpox on board. Port health authorities whether they are concerned with a seaport or airport have one major function and that is to protect the country of which they are the...

A change of the guard.