ABSTRACT
Plants and animals are compared with reference left-right symmetry. This type of symmetry is a fairly common feature in both plants and animals, distributed across their different groups. In both groups, there are internal and external asymmetries, the former being more common in animals and the latter in plants. Left-right symmetry plays an important role in reproduction in both animals and plants; particularly in plants, it is likely to promote out-crossing. The phenomena of antisymmetry and directional asymmetry are known in both groups; the former is not inherited while the latter is inherited. The role of genetics, environment, and chance (stochastic factor) in symmetry/asymmetry is discussed. The need for more studies in plants, in comparison to animals, is emphasized.
