Light-triggered closing of the cGMP-gated cation

channels causes a drop in the cytosolic Ca2+ concentration inside the rod cell.

TLS Online TPP Program

#Id: 10803

#XL - R Botany

Phenolic compounds

Flavonoids may protect against damage by ultraviolet Light

Isoflavonoids have antimicrobial activity

Isoflavonoids are found mostly in legumes such as the rotenoids, have strong insecticidal actions; others have anti-estrogenic effects. 

For example, sheep grazing on clover rich in isoflavonoids often suffer from infertility

TLS Online TPP Program

#Id: 10804

#XL - R Botany

phytoalexins, antimicrobial compounds synthesized in response to bacterial or fungal infection that help limit the spread of the invading pathogen.

TLS Online TPP Program

#Id: 10805

#XL - R Botany

Tannins deter feeding by herbivores

Plant tannins also serve as defenses against microorganisms.

For example, the nonliving heartwood of many trees contains high concentrations of tannins that help prevent fungal and bacterial decay

TLS Online TPP Program

#Id: 10806

#XL - R Botany

Nitrogen - containing compounds

TLS Online TPP Program

#Id: 10807

#XL - R Botany

TLS Online TPP Program

#Id: 10808

#XL - R Botany

Various nitrogenous protective compounds other than alkaloids are found in plants.

Two groups of these substances— cyanogenic glycosides and glucosinolates—are not in themselves toxic but are readily broken down to give off volatile poisons when the plant is crushed