Distinguish between prokaryotic cells and eukaryotic cells:
Prokaryotic and Eukaryotic are two different types of cells and both are completely different from each other. In this article, we explain all the differences between Prokaryotic and eukaryotic cells so that you can distinguish them perfectly in your preparation. Before starting let us know about concepts of what is cells and the similarities between prokaryotic cells and Eukaryotic cells.
What is a Cell?
As we know the body of all organisms from the simplest to the most complex one is made up of many microscopic units which carry out the various processes that make the organisms living things. Such Basic structural and functional unit of the living body which are able independent existence is called a cell. All living things are composed of cells. A cell is the structural and functional unit of every living organism, capable of independent existence.
In living organisms, all functions are performed by the cell. Many organisms are Single cells called unicellular with the whole body comprising a single, free-living cell. These organisms are mostly microscopic, such as bacteria, Amoeba, Euglena, Chlamydomonas, etc. Other organisms (animals from sponges to mammals, most algae, fungi, plants, and trees) are multicellular (many cells). All these organisms differ in their structure, functions, and behavior. Since all life activities of an organism are present in miniature form in every cell, therefore, it is called a basic unit of life.
There are of two types cells based on the organization of DNA (nucleus), the organization of biomembranes, and a variety of membrane-bound cytoplasmic organelles. These are prokaryotic cells and eukaryotic cells. Prokaryotic cells contain 3 types of organisms blue green algae, bacteria, and PPLO (Pleuropneumonia like organisms) whereas the other organisms except the above three are included in eukaryotic cells.
The prokaryotic cells are morphologically the most primitive cells which means they lack true nuclei and membrane-bound cell organelles. They seem to have appeared about 3.5 billion years ago. A prokaryotic cell is essentially a single-membrane or one-envelope system. The membrane surrounds the cell. There is no membrane enveloping the genetic material and the membranes pervading the cytoplasm are scarce, if present they are usually associated with respiration or photosynthesis.
The eukaryotic cells have a more elaborate internal organization than the prokaryotic cells. A eukaryotic cell is essentially a double membrane or two-envelope system. The primary membrane surrounds the cell. Secondary membranes envelop the nucleus and certain other subcellular organelles and also pervade the cytoplasm. The eukaryotic cells occur in protists, fungi, plants, and animals. These organisms are called eukaryotes. The eukaryotic cells are of two types-plant animal cells. Most of the organelles and other structures of cells are common to animal cells and plants cell. Prokaryotic and eukaryotic cells possess some basic similarities and differences described in detail in the table given below :
Similarities Between Prokaryotic Cell and Eukaryotic Cell:
Apart from the differences seen, there are also some similarities between eukaryotic and prokaryotic cells :
- DNA is found in both prokaryotic and eukaryotic cells.
- Protoplasm is found in both prokaryotic and eukaryotic cells.
- Photosynthesis occurs in both prokaryotic and eukaryotic cells.
- Cell membranes are found in both prokaryotic and eukaryotic cells.
- The cell wall is present in both prokaryotic and eukaryotic cells. The cell wall in prokaryotic cells is made of peptidoglycan and in eukaryotic cells, the cell wall is made of cellulose.
- The 70s ribosome is found in prokaryotic cells and the 80s ribosome is found in eukaryotic cells.
- Both eukaryotic and prokaryotic cells are the basic and fundamental units of life on Earth. Thanks to them, every one of the different unicellular and multicellular organisms has been able to evolve and colonize the different habitats on the planet.
- Both types of cells are characterized by being structures delimited by membranes that inside retain their DNA or genetic information as well as different enzymatic machinery that allows them to develop their vital functions: feeding, growth, and reproduction.
- To survive and evolve, eukaryotic and prokaryotic cells constantly convert energy from one form to another, in addition to maintaining a continuous relationship with their exterior, to respond to the different sources of chemical-biological information that they receive from the environment.
Difference between Prokaryotic cell and Eukaryotic Cell Pdf :
| Prokaryotic Cell | Eukaryotic Cell |
|---|---|
| The Cell which carries a primitive or undeveloped nucleus is called a prokaryotic cell. | The cell which carries a true or developed nucleus is called a eukaryotic cell. |
| The size of the cell generally ranges from 0.2 micrometers to 2.0 micrometers in diameter | Eukaryotic cells range from 10 to 100 micrometers in diameter. |
| Simpler in structure | More complex in comparison to prokaryotic cells |
| The organelles in prokaryotic cells are not membrane-bound | The organelles in eukaryotic cells are certainly specific in function. Most noteworthy, they are membrane-bound |
| In this cell true nucleus is absent, instead, a nucleotide is present | The true nucleus is present. |
| DNA is arranged in a circular shape | DNA is linear in shape |
| In prokaryotic cells, the cytoplasm is present, but it is lacking in most cell organelles. | In eukaryotic cells, it consists of both cytoplasm and organelles, both are present. |
| The cell wall is present here. Furthermore, it comprises mucopeptide or peptidoglycan | Usually, a cell wall is absent here. However, in case it is present, it comprises cellulose |
| Cell division occurs through binary fission, transduction, conjugation, and transformation | Cell division occurs through mitosis |
| Mitochondria is absent | Mitochondria is present and it is a powerhouse of cells. |
| The endoplasmic reticulum is not present in prokaryotic cells. | The endoplasmic reticulum is present in eukaryotic cells. |
| The ribosome is present Smaller size 70S, distributed in the cytoplasm. | Larger size 80s, found on membranes as in endoplasmic reticulum; 70s present in organelles such as chloroplast and mitochondria. |
| Plasmids are commonly found in prokaryotes. | Plasmids are very rarely found in eukaryotes |
| In these cells, only asexual reproduction occurs. | Both sexual and asexual reproduction occurs. |
| These cells have a single origin of replication | These cells have multiple origins of replication |
| Only one chromosome is there in a prokaryotic cell. | There are many chromosomes present in the eukaryotic cells. |
| Bacteria and Archaea are the major examples of prokaryotic cells. | Plant cells and animal cells are the major examples. |
Frequently Asked Questions on the difference between Prokaryotic and eukaryotic cells:
1. Name the smallest-sized organism.
Answer: The smallest known organism is mycoplasma or pleuropneumonia-like organism (PPLO). its size is around 0.1 to 0.5 um.
2. Who discovered cells and how?
Answer: Robert Hooke in 1665 discovered the cells. He examined thin slices of cork under a self-designed primitive microscope and saw that the cork resembled the structure of a honeycomb. The latter consisted of many tiny compartments. He called them cellulae (singular cellula), now termed cells. Cellula is a Latin word that means hollow space or compartment.
3. Write the similarities and differences between prokaryotic cells and eukaryotic cells?
Answer :
Similarities Between Prokaryotic and Eukaryotic Cell :
- They both have DNA.
- Both are surrounded by a plasma membrane.
- They both have ribosomes.
- They have a cell wall.
- They are cells
- They have a nucleus.
Differences between Prokaryotic and Eukaryotic Cell :
- In prokaryotic cells, the genetic material is not separated from the cytoplasm.
- Eukaryotes present the genetic material organized in chromosomes surrounded by a membrane that separates them from the cytoplasm.
- Eukaryotes have a nucleus. Prokaryotes do not have nuclei.
- Prokaryotic cell organelles are not membrane bound while eukaryotic cell organelles are membrane bound.