Expert: Walter Hintz - 4/12/2006

Question
Hi there Walter,

I was watching a show on prokaryotes and eukaryotes and it said that they are what everything came from (living that is). The question that interested me is what makes us? Humans? What is our organs made of? Or our skin? Are cells alive and do they reproduce sexualy, asexualy? What is the heart made of? Is it also of tons of prokayotes that live in colonies?

I know these questions some ridiculous, but I never took Biology in High School, nor college.

If you can answer these question I would apprechiate it.


Thanks a million!!!

Answer
Hi Sam:
Evidence tells us that life forms began from single cells and the firtst cells were prokaryotes.  These cells had no nucleus and they are still around today as bacteria. Eventually prokaryotes developed nuclei and other structures and eukaryotes appeared.
 All living organisms are made up of cells including you and I and our cells are eukaryotic.  There different kinds of these cells such as skin cells, nerve cells, bone cells, muscle cells etc.. The cells make up tissues and the tissues make up organs. Cells reproduce themselves by dividing asexually. New individuals develop from sexual reproduction when special cells (sperms and eggs) join togrther.  They form a eukaryotic cell that starts dividing and the new cells differentiate into the different types of cells that make up a new individual.

Your questions are not ridiculous