Venom organ failure. Many caterpillars have defensive venom glands associated with specialized bristles on the body, known as urticating hairs, which can be lethal to humans (e.g., that of the "Lonomia" moth), although the venom's strength varies depending on the species. Bees synthesize and employ an acidic venom (apitoxin) to cause pain in those that they sting to defend their hives and food stores, whereas wasps use a chemically different alkaline venom designed to paralyze prey, so it can be stored alive in the food chambers of their young. The use of venom is much more widespread than just these examples.
Dilute Russell's viper venom time Dilute Russell's viper venom time Dilute Russell's viper venom time (dRVVT) is a laboratory test often used for detection of lupus anticoagulant (LA). This "in vitro" diagnostic test is based on the ability of the venom of the Russell's viper to induce thrombosis. The venom contains some substances (RVV-V and RVV-X) which directly activate factor V and factor X, which turns prothrombin into thrombin in the presence of phospholipid and calcium. In the dRVVT assay, low, rate-limiting concentrations of both Russell's viper venom and phospholipid are used to give a standard clotting time of 23 to 27 seconds. This makes