Remember that prokaryotic cells are simple and do not contain membrane-bound organelles and that eukaryotic cells are more complex and do contain membrane-bound organelles, as well as a nucleus. The endosymbiosis theory explains how eukaryotic cells may have evolved from prokaryotic cells. Symbiosis is a close relationship between two different organisms. We saw that, over time, one ancient cell became the host for other ancient cells that were capable of specific activities.
aviary, An aviary is a large enclosure for confining birds. Unlike cages, aviaries allow birds a larger living space where they can fly; hence, aviaries are also sometimes known as flight cages. Aviaries often contain plants and shrubbery to simulate a natural environment.
What is Varnish. Varnish is a general name, like paint, for a transparent, protective finish or film mostly used on wood. Traditional Varnishes contained a resin, a drying oil, and a solvent. The finish is usually shiny but can be modified by adding flatting agents or by rubbing the hardened varnish with abrasives.Varnish is transparent, but often has a yellowish tone.raditional Varnishes contained a resin, a drying oil, and a solvent. The finish is usually shiny but can be modified by adding flatting agents or by rubbing the hardened varnish with abrasives. Varnish is transparent, but often has a yellowish tone.