Origin of Eukaryotes
Theory of Endosymbiosis
The evolution of eukaryotes has no fossil record. However, from the study of modern organisms, biologists deduced their theory that eukaryotes evolved from prokaryotes through the endosymbiosis process. The state of one species living inside another species, known as the host, is called endosymbiosis.
Eukaryotes evolved from the Archaea domain of prokaryotes, whereby prokaryotic cell have engulfed aerobic bacteria instead of engulfing other prokaryotes. Membrane infolding is the first process that occurs in the development of eukaryotic cell. Around the nucleus, nuclear envelope is formed due to the inward folding of the plasma membrane. Later, attached to the nuclear envelope, endoplasmic reticulum is produced. The development process of mitochondria and chloroplasts completes the formation of eukaryotic cell.
Some of the researched evidences of biologists...
Given a mosquito's vastly shorter life span, preventing the spread of the infection to more human hosts greatly reduces the number of viable parasites in existence (CDC 2009). 10) There are several reasons that viral infections are more difficult to treat and diagnose than bacterial infections. For one thing, viruses are not truly alive, and this makes it difficult to kill them. They are essentially packets of genetic information in tough
In one laboratory experiment, bacteria exposed to high levels of pathogenic bacteria over several hundred generations eventually adapted "their progeny became dependent on having the formerly pathogenic bacteria in food vacuoles...(Jeon, 1991)" (Armstrong) There are several ways in which bacteria may subsume other bacteria, including ingesting them and maintaining them in food vacuoles as in the Jeon experiment, or they may become infected by bacteria that are acting as
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