Differentiate between eukaryotes and prokaryotes.

Question

What will be an ideal response?

Answer 1

The simplest living cell is called a prokaryote (pro-CARRY-oat), which means a cell without a nucleus. Even though it has no nucleus, a prokaryote is already highly complex. A membrane encloses all of its contents and regulates molecular traffic in and out. The content of the cell, except for the genetic material, is called cytoplasm; it is made up primarily of proteins, which are long chains of amino acids folded into a three-dimensional (3-D) shape. New proteins are constructed at special structures in the cell’s cytoplasm called ribosomes. In prokaryotes the genetic material, the DNA molecule, floats around not enclosed in a membrane that would form a nucleus.

2.5 to 1.5 billion years ago, partly as a consequence of developing respiration, a new kind of cell emerged among the mats of stromatolites. The earliest evidence for this new kind of cell comes fromabout 1.8 billion years ago. It may have appeared much earlier, but the earlier history of life is controversial dueto gene transfer among the three domains and the sheer difficulty of finding evidence. This new cell proved to bea momentous increase of complexity, and no other cell innovationhas appeared since.

This new cell, called a eukaryote(you-CARRY-oat),differs from a prokaryote in various ways. Eukaryotes aremuch larger than prokaryotes, 10 to 1,000 times larger.Their DNA is enclosed in a protective membrane that constitutesa well-developed nucleus. The cell is large enough The larger cells apparently ingested the mitochrondria andchloroplasts but did not digest them. This aspect of eukaryoteswas not understood until biologist Lynn Margulisproposed it in 1967, strongly indicating that evolution proceedsby cooperation as well as by competition. Biologistsnow largely accept her idea, in part because mitochondriacarry their own DNA.
Some eukaryotes are single-celled—for example, diatomsor microscopic algae. Others are multicellular—forexample, all the eukaryotic cells in human bodies.