The M C M 2 - 7 proteins form a six-member ring-shaped complex around DNA. MCM 2, 3, 5 are regulatory, while MCM4,6,7 have helicase activity.

TLS Online TPP Program

#Id: 9723

#Unit 6. System Physiology – Plant

Trichomes of nettles (Urtica dioica) have “cocktail” of secondary metabolites that can cause severe irritation of the skin of animals.

TLS Online TPP Program

#Id: 9724

#Unit 6. System Physiology – Plant

Calcium oxalate crystals are present in the vacuoles of many species, and may be distributed evenly throughout the leaf or restricted to specialized cells called idioblasts

TLS Online TPP Program

#Id: 9725

#Unit 6. System Physiology – Plant

Constitutive chemical defenses are effective against many different herbivores, including insects and mammals. 

TLS Online TPP Program

#Id: 9726

#Unit 6. System Physiology – Plant

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

TLS Online TPP Program

#Id: 9727

#Unit 6. System Physiology – Plant

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

#Unit 6. System Physiology – Plant

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).