Prokaryotic organisms have a single origin of replication, whereas eukaryotic organisms have many origins where replication occurs simultaneously. which of the following is the most probable reason for this observation?
prokaryotic dna is much smaller than eukaryotic dna.
prokaryotes do not replicate their dna.
prokaryotic dna is single-stranded.
prokaryotic dna is replicated more slowly than eukaryotic dna.

The correct answer is: Prokaryotic DNA is much smaller than eukaryotic DNA.

The first difference between prokaryotic and eukaryotic genome is its structure and complexity: Prokaryotic cells have a small amount of DNA in the form of a single, circular chromosome located in the cytoplasm, while eukaryotic cells have a nucleus and DNA arranged in multiple, linear chromosomes in it; eukaryotic cell has about 25 times more DNA than a prokaryotic cell. Differences in replication between prokaryotic and eukaryotic cells:

•point of origin

•direction- replication occurs in two opposing directions in prokaryotes while in eukaryotes it is unidirectional

•polymerases- in prokaryotes there are only one or two enzymes polymerases, while in eukaryotes four or more

•faster rate in prokaryotic cells.

hydroxyl -oh

alcohols, always polar, can form hydrogen bonds with h2o molecules

carboxyl -cooh  

cargoxylic acids, has acidic properties which is a source of hydrogen ions, found in cells in ionized for with a charge of oh-1

carbonyl > co

ketone if within skeleton, aldehyde if group is at the end of skeleton, k & a may be structural isomers, it determines 2 sugars (ketose & aldose)

amino -nh2

amines, acts as a base, it can pick up h+ ions from surrounding solution, ionized with charge of 1+

methyl ch2

addition to rna/dna affects and gene expression

phosphate -opo3 ²⁻

organic phosphates, contributes to negative charge to, molecule that it is a part of, and potential to react with h20

sulfhydryl -sh

thiols, cross-linking stabilize the protein, and it is structure