"Eukaryote" roughly translates as "truly nucleated" and refers to organisms with a membrane-bound nucleus.
Such membrane-bound organelles are thought to have arisen via the invagination of the cell's own plasma membrane.
Other organelles such as the mitochondria and the chloroplast are believed to have once existed as separate organisms, but which were engulfed by other cells, forming a symbiotic relationship.
It was affected by natural selection.
If this is wrong someone please tell me.
When two indistinguishable crickets are together, for example, and you only know they are different because of their mating song. A behavioral isolational cricket would conduct only that with another cricket with similar mateship behavior.
BTW you should probably put in the options.
This is true. A<span> chromosome has to have more than one gene.</span>