Theory of recapitulation - Ernst Haeckel

He proposed that the embryonic development of an individual organism (its ontogeny) followed the same path as the evolutionary history of its species (its phylogeny).

TLS Online TPP Program

#Id: 9726

#XL - R Botany

Hemlock (Cicuta sp.) produces cicutoxin, a polyacetylene that prolongs the repolarization of neuronal action potentials.

TLS Online TPP Program

#Id: 9727

#XL - R Botany

The active principle in foxglove (Digitalis sp.) is cardinolide digitoxin, a cardiac glycoside that inhibits ATPase activity and can increase myocardial contraction.

TLS Online TPP Program

#Id: 9728

#XL - R Botany

Laticifers are made of individual cells and can occur either as articulated systems (single cells connected by a small tube) or non-articulated systems (one large syncytial cell).

TLS Online TPP Program

#Id: 9729

#XL - R Botany

Latex are resin terpenoids produced by laticifers is released upon damage and often contains cardiac glycosides which fend off herbivores.

TLS Online TPP Program

#Id: 9730

#XL - R Botany

Conifer resin ducts produces bicyclic monoterpenes such as a-pinene and b-pinene, monocyclic terpenes like limonene and terpinolene, and tricyclic sesquiterpenes, including longifolene, caryophyllene, and d-cadinene, as well as resin acids, which are released immediately upon damage by herbivores

TLS Online TPP Program

#Id: 9731

#XL - R Botany

The specialist caterpillars of the monarch butterfly

(Danaus plexippus) are insensitive to the terpenoid toxins. They feed on milkweed leaves and retain the cardenolides. As a result, most insectivorous birds quickly learn to avoid eating monarch caterpillars and adult monarch butterflies.