Difference between Prokaryotic and Eukaryotic cells

The cell is the basic unit of organization or structures of all living matter. Cell is the smallest portion of an organism which exhibits range of properties of living beings like reproduction, mutation, metabolism and sensitivity. Cell is defined as “a unit of biological activity delimited by a semi permeable membrane and capable of self reproduction in a medium free of other living systems.”
The body of all living organisms (bacteria, blue green algae, plants and animals) except viruses has cellular organization and may contain one or many cells. The organisms with only one cell in their body are called unicellular organism (e.g., bacteria, blue green algae, some algae, protozoa etc). The organisms having many cells in their body are called multicellular organisms (plants and animals). 
Read more: Unicellular vs Multicellular Organism
There are two main classes of cells, namely:
(A) Prokaryotic cell
(B) Eukaryotic cell
The terms prokaryotic and eukaryotic were suggested by Hans Ris in the 1960’s. The prokaryotes consists of the bacteria and blue green algae and were first to arise in biological evolution (i.e., about 3 x 10 9 years old). The eukaryotic cells are found in all multicellular animals, plants and fungi. Eukaryotes have arisen probably a billion year after the prokaryotes and much larger and complex. They show a wide range of diversity and differentiation.
Prokaryotic and Eukaryotic cell








No







Features
Prokaryotic Cell

Prokaryotic Cell
Prokaryotic Cell

Eukaryotic cell

Eukaryotic cell
Eukaryotic cell




1


Occurrence

Prokaryotic cells are the characteristics of bacteria and blue green algae (cyanobacteria)


These are cells are  found in all, animals and plants, except blue green algae and bacteria.


2

Size

Mostly 1-10 μm

Mostly 10-100 μm


3

Multicellular forms


Rare

Common, with extensive tissue formation


4

Present in most but not in all cells. In Bacteria, cell wall is made up of murein, poly saccharides, lipids and proteins. Read more


The animal cells lack cell wall, but plants cell wall is made up of cellulose and chitinous cell wall is present in fungi. Read more

5

Present

Present


6

Absent. Nucleiod region is present where genetic material resides.


Present

7

Nuclear Membranes


Absent

Present

8

Chromatin with histone


Absent

Present


9

Each cell has only one chromosome.

Number of chromosomes per cell depends upon the type of organism.



10

The chromosome is circular ring lacking a centromere.

Each chromosome is linear having a centromere with two kinetochores meant for attachment to the spindle  fibres during cell division.




11

Circular or linear, double stranded DNA: only exons are present

Linear double stranded DNA: genes frequently interrupted by intron sequences, especially in higher eukaryotes (called as split genes).


12

Nucleoli and Mitotic  apparatus


Absent

Present

13

Absent

Present (for the synthesis and organisation of ribosomes)


14

Commonly present

Rare



15


Mesosomes

Mesosomes perform the function of golgibodies and mitochondria, and also help in the separation of chromosomes during cell division.



Absent












16
Cell organelles

Absent

Present


Absent

Present


Vacuoles


Absent

Present


Absent

Present


Absent

Present
(Only in plants)


Centrioles

Absent

Present
(Absent in higher plants)


Only 70S type of ribosomes are present which lie free in cytoplasm, or are engaged in protein synthesis.


The cytoplasm has 80S type of ribosomes; and plastid and mitochondria have 70 S type of ribosomes


Absent

Present


Flagellae

Simple structure composed of the protein Flagellin. Read more

Complex 9+2 structure of tubulin and other protein. Read more


17

Respiration

Many strict anaerobes

All aerobic, but some facultative anaerobes by secondary modifications.


18

Photosynthetic Enzymes

Bound to plasma membrane as composite chromatophores

Enzymes packed in plastids bound by membrane



19


Metabolic Patterns


Great Variations

All share cytochrome electron transport chains, Krebs cycle oxidation, Embden-Meyerhof glucose metabolism or glycolysis.




20




Sexual System

Rare: If present one way (and usually forming partial diploids or merozygotes); transfer of DNA from donor to recipient cell occurs (conjugation). Gene transfer takes place by transformation and transduction also.

Both sexes involved in sexual participation and entire genomes transferred; alternation of haploid and diploid generations is also evident.


21

Cyclosis


There are no streaming movements of cytoplasm

Cytoplasm shows streaming movements

22

Protein Synthesis

Transcription and translation take place in cytoplasm.

Transcription occurs in nucleus and translation takes place in cytoplasm.


23

Duration of cell cycle

Cell cycle is short, takes 20-60 minutes to complete.

Cell cycle is long, takes 12-24 hours to complete.

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