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The transformation efficiency is lower than in Agrobacterium-mediated transformation, but most plants can be transformed with this method. Electroporation : Formation of transient holes in cell membranes using electric pulses of high field strength; this allows DNA to enter as described above for bacteria.
Palatal and nasal skeletal features like choanae are present in these groups and are also observed in modern amphibians. This indicates that incipient air breathing was developed, as well as modification of the hyoid arch towards stapes development. [5] These characteristics account for why osteichthyans are accepted as the sister group of ...
Hyder, Avery, MacLeod and McCarty used strands of purified DNA such as this, precipitated from solutions of cell components, to perform bacterial transformations. The Avery–MacLeod–McCarty experiment was an experimental demonstration by Oswald Avery, Colin MacLeod, and Maclyn McCarty that, in 1944, reported that DNA is the substance that causes bacterial transformation, in an era when it ...
The Scientific Revolution was a series of events that marked the emergence of modern science during the early modern period, when developments in mathematics, physics, astronomy, biology (including human anatomy) and chemistry transformed the views of society about nature.
A dragonfly in its final moult, undergoing metamorphosis, it begins transforming from its nymph form to an adult. Metamorphosis is a biological process by which an animal physically develops including birth transformation or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. [1]
Transmutation had previously been used as a term in alchemy to describe the transformation of base metals into gold. Other names for evolutionary ideas used in this period include the development hypothesis (one of the terms used by Darwin) and the theory of regular gradation , used by William Chilton in the periodical press such as The Oracle ...
Initial theories of transformation of materials were developed by Greek philosophers, such as the Four-Element Theory of Empedocles stating that any substance is composed of the four basic elements – fire, water, air and earth. In the Middle Ages, chemical transformations were studied by alchemists.
Cave paintings (such as this one from France) represent a benchmark in the evolutionary history of human cognition. Victorian naturalist Charles Darwin was the first to propose the out-of-Africa hypothesis for the peopling of the world, [40] but the story of prehistoric human migration is now understood to be much more complex thanks to twenty-first-century advances in genomic sequencing.