There are several key differences between prokaryotic and eukaryotic genomes and cells. Prokaryotes have a single circular genome located in the cytoplasm, while eukaryotes have multiple linear genomes located within the nucleus. Prokaryotes also lack membrane-bound organelles, cytoskeletons, and complex cellular structures like mitochondria and chloroplasts that eukaryotes have. Additionally, prokaryotes reproduce through binary fission while eukaryotes undergo mitosis and meiosis, and prokaryotes lack true sexual reproduction seen in eukaryotes involving male and female participation.

1. Difference between prokaryotic and
eukaryotic genome

2. Genome
Prokaryotes Eukaryotes
Single,
Circular
Multiple,
Linear

3. Location of genome
Prokaryotes Eukaryotes
Cytoplasm
Haploid or merodiploid
Plasmids are commonly found
More compact
Telomers are absent
Introns are absent
Repetitive DNA absent
Transcription and translation occur
simultaneously
Inside the nucleus
Diploid
Plasmids are not observed
Less compact
Telomers are present
Introns are present
Repetitive DNA present
Transcription takes place in nucleus and
translation occur in the cytoplasm

4. Ratio of genomic to non genomic DNA
Prokaryotes Eukaryotes
Over 90 % protein coding genes, little
nongenetic DNA , no pseudogenes
almost no repeats
Horizontal gene transfer
Homologous recombination and
chromosome, up to 5-10 % protein
coding genes, abundance of nongenetic
DNA-pseudogenes, and different repeats
segregation linked to reproduction

5. Cell division
Prokaryotes Eukaryotes
No mitosis or meiosis
Binary fission or budding
Evolution is based on the rapid
proliferation and accumulation of
mutations and hypermutations
Mitosis and meiosis occur in cells
High contents of repeats facilitates the
recombination's, translocations,
shuffling's, duplications, and
rearrangements of different scales

6. Sexual reproduction and crossing over
Prokaryotes Eukaryotes
True sexual reproduction is absent
Through conjugation genetic material is
transmitted to another organism
May have pili and fimbriae
No histone proteins are found
Lack cytoskeleton
Trans acting elements absent
Distal acting elements absent
True sexual reproduction is present and male and
female participation is equal
May have cilia
DNA is wound around the histone proteins
Cytoskeleton made of actin and microtubules
Trans acting elements are present
Distal acting elements are present

7. Flagella
Prokaryotes Eukaryotes
Have simple structure with 9 +0 arrangement
Flagellin protein
Have complex structure and have 9+2
arrangement of microfibrils

8. Cell wall
Prokaryotes Eukaryotes
Bacterial cell wall – peptidoglycan Plant cell wall- cellulose
Animals – lack cell wall
Fungi- chitin, cellulose

9. Cell organelles
Prokaryotes Eukaryotes
Membrane bound organelles such as endoplasmic
reticulum, Golgi complex, mitochondria,
chloroplasts and vacuoles are absent
Ribosomes 70S
Membrane bound organelles such as endoplasmic
reticulum, Golgi complex, mitochondria,
chloroplasts, vacuoles are present
Ribosomes 80 and 70S

10. • All cellular activities are encoded within a cell’s DNA. The sequence of bases
within a DNA molecule represents the genetic information of the cell.
• Segments of DNA molecules are called genes, and individual genes contain the
instructional code necessary for synthesizing various proteins, enzymes, or stable
RNA molecules.
• The full collection of genes that a cell contains within its genome is called
its genotype.
• However, a cell does not express all of its genes simultaneously. Instead, it turns
on (expresses) or turns off certain genes when necessary.

11. • The set of genes being expressed at any given point in time determines the cell’s
activities and its observable characteristics, referred to as its phenotype.
• Genes that are always expressed are known as constitutive genes; some
constitutive genes are known as housekeeping genes because they are necessary
for the basic functions of the cell.
• While the genotype of a cell remains constant, the phenotype may change in
response to environmental signals (e.g., changes in temperature or nutrient
availability) that affect which nonconstitutive genes are expressed.

12. • For example, the oral bacterium Streptococcus mutans produces a sticky slime
layer that allows it to adhere to teeth, forming dental plaque; however, the genes
that control the production of the slime layer are only expressed in the presence of
sucrose (table sugar).
• Thus, while the genotype of S. mutans is constant, its phenotype changes
depending on the presence and absence of sugar in its environment.
• Temperature can also regulate gene expression. For example, the gram-negative
bacterium Serratia marcescens, a pathogen frequently associated with hospital-
acquired infections, produces a red pigment at 28 °C but not at 37 °C, the normal
internal temperature of the human body

13. Mechanisms if control of genes in bacteria
• Bacteria have very simple general mechanisms for coordinating and
regulation of genes that encode products involved in a set of related
process
• The gene cluster and promoter plus additional sequences that function
together are called an operon