Plants do not rely on a single defence mechanism, but rather express multiple defences comprising the constitutive and induced synthesis of many chemical compounds as well as the production of structural traits [e.g. 21] [24].
Our results suggest that Daphnia which express inducible defences against smaller invertebrate predators suffer more from an additional stressor, here parasites, than Daphnia expressing inducible defences against large vertebrate predators, at least for the traits measured in this study.
It has been shown that Daphnia galeata can still express inducible defences against fish, regardless of infection with protozoan or yeast parasites [ 23, 24].
Similar tests have been made in only a limited number of systems, but given that induced defence is found even in this species that possesses constitutively expressed chemical defence, it may well be a ubiquitous feature of higher plants.
(Plantinga originally expressed his defence of properly basic theistic belief in terms of the rationality of believing in God 'without any evidence or argument at all' (Plantinga 1983, 17).
They are constitutively expressed; thus, defence mechanisms are readily available and need not be upregulated.
The transgenic plants also constitutively expressed the defence response genes, PR-1 and PDF1.2.
Like H. pylori [ 39], because of its microaerophilic requirements, H. bizzozeronii expresses several defence mechanisms against oxidative stress.
During this period of immune suppression the endometrium would be expected to be susceptible to infections; the endometrium must, therefore, actively express specific molecules for defence against foreign pathogens.
