Digitalis purpurea range of colours from white through pink to purple, such as "Dalmatian Purple". Cultivated forms often show flowers completely surrounding the central spike, in contrast to the wild form, where the flowers only appear on one side. "D. purpurea" is easily grown from seed or purchased as potted plants in the spring. The following selections have gained the Royal Horticultural Society's Award of Garden Merit: "Digitalis purpurea" is hardy to zones 4-9. Digoxigenin (DIG) is a steroid found exclusively in the flowers and leaves of the plants "Digitalis purpurea" and "Digitalis lanata". It is used as a molecular probe to
Plant physiology plants produce a vast array of chemical compounds with unique properties which they use to cope with their environment. Pigments are used by plants to absorb or detect light, and are extracted by humans for use in dyes. Other plant products may be used for the manufacture of commercially important rubber or biofuel. Perhaps the most celebrated compounds from plants are those with pharmacological activity, such as salicylic acid from which aspirin is made, morphine, and digoxin. Drug companies spend billions of dollars each year researching plant compounds for potential medicinal benefits. Plants require some nutrients, such as carbon and