<u>Answer</u>: Bacteria through the nucleoid (number 5).
<u>Explanation</u>:
Both paramecium and bacteria are single celled organisms. However, they differ by the fact that the first one is an eukaryote and the second one a prokaryote.
Furthermore, they differ in their capacity to mutate and adapt to environmental changes. Bacteria have a simple internal structure that lacks any organelles and are very adept at adapting to environmental changes. Besides their capacity for high mutation rates, they are also capable of picking up genetic information from their environment through a process called <em>transformation</em>.
Through transofrmation, environmental DNA enter the living bacteria through its cell membrane. Double stranded DNA will have one strand dissolved through hydrolysis, whereas the second strand may recombine with the bacterial <em>chromosome (nucleoid)</em>. Thus, this new genetic material will become incorporated into the bacterium's genome.
<span>Yeast cells reproduce quickly by budding. This is a form of asexual reproduction so all the yeast cells are identical.
Hope this helps!</span>
The correct answer is - No.
The Cambrian explosion is a term used for the big and rapid diversification of the animal species, but it is not the period in which the animal life started. The animal life started in the period between 620 and 550 million years ago, in what is known as the Vendian Period. In the Vendian Period, the first complex animal organisms appeared, started to develop and evolve, though it is not a period where there was a high diversification of the species. The later Cambrian Period provided better living conditions, and that resulted in a so called ''explosion of life'', which resulted in much more new species developing and evolving.