There are multiple types of dystonia, and numerous diseases and conditions may cause dystonia.
Oak is the most common name for trees listed in the genus Quercus. There are a few species that exhibit a shrub type growth form instead of a tree form.There are both deciduous and evergreen species and some are semi-evergreen.Currently there are approximately 600 different species listed in the Quercus (Oak) genus.The tree name  Oak  is also used for the common names of some species in related genera, especially those listed in the Lithocarpus genus.ome evergreen Oak trees (especially certain American Species) are given a grouping common name called Live Oak. This name applies to different species that have an evergreen growth habit, and does not reflect any taxonomic classification group, as these species are distantly related in some cases.
An oak is a tree or shrub in the genus Quercus of the beech family, Fagaceae. There are approximately 600 extant species of oaks. The common name oak also appears in the names of species in related genera, notably Lithocarpus, as well as in those of unrelated species such as Grevillea robusta and the Casuarinaceae. The genus Quercus is native to the Northern Hemisphere, and includes deciduous and evergreen species extending from cool temperate to tropical latitudes in the Americas, Asia, Europ