Will advanced organisms be the same as complex organisms? Why?

The speed of binary fission in Escherichia coli is : (a) considerably slower than mitosis of advanced organisms since bacteria are primitive (b) considerably faster than mitosis of advanced organisms (c) essentially the same speed as mitosis in advanced organisms since the need to build DNA and new cell components is the same in both organisms (d) none of the above

What are we referring to when we say 'simple organism ' or ' complex organism' ?

What are we referring to when we say 'simple organism ' or ' complex organism' ?

Why do organisms reproduce ?

What are we referring to when we say 'simple organisms' or 'complex organisms'?

The organisms which physically and chemically break the complex organic remains are known as

Why do organism reproduce ?

Why do organisms of same species look similar ?

What are we referring to when we say 'simply organisms' or 'complex organism'?