Difference between Prokaryotic and Eukaryotic Cell
Key difference: The main difference between the two cells is that prokaryotic cells basically have no nuclei, whereas eukaryotic cells do have true nuclei. Eukaryotic cells are larger and more complex than the prokaryotic cells.
include("ad4th.php"); ?>All living organisms can be sorted into one of two groups depending on the fundamental structure of their cells. The two main classes of cells are the prokaryotes and the eukaryotes. These two cell types have a lot in common. They perform the same kinds of functions, and in the same ways. Both are enclosed by plasma membranes, filled with cytoplasm, and loaded with small structures called ribosome. Both have DNA which carries the archived instructions for operating the cell. However, there are a few differences between the two types of cells.
The term prokaryote is derived from the Greek word “prokaryote”, which means before nuclei. Prokaryotes are organisms made up of cells that lack a cell nucleus or any membrane-encased organelles. This means that they have no nucleus. Also, the genetic material, i.e. DNA, in prokaryotes is not bound within a nucleus. Additionally, the DNA is less structured and is in a single loop. Most prokaryotes are made up of just a single cell and are called as unicellular organism. There are also a few prokaryotes which are made of collections of cells and are called as multi-cellular organisms. The prokaryotes are divided into two groups, they are:
- Bacteria
- Archaea
Eukaryotes are organisms made up of cells that possess a membrane-bound nucleus as well as membrane-bound organelles. The term eukaryote is derived from the Greek word “œeukaryoteâ”, which means true or good nuclei. This cell includes all life kingdoms except monera. These organisms hold the genetic material in their cells. The genetic material in eukaryotes is contained within a nucleus in a cell. The DNA of these organisms is structured and is organized into chromosomes. Also, the DNA is linear and is associated with proteins to form chromatin. Eukaryotic organisms may be multi-cellular or single-celled organisms. All animals are considered as eukaryotes. Other eukaryotes include plants, fungi, and protists.
Prokaryotic and Eukaryotic cells are both associated with each other in size and complexity. These cells are different from each other. However, they are clearly more alike than different, and they are clearly evolutionarily related to each other. Biologists believe that the eukaryotic cell is clearly developed from the prokaryotic cell.
Comparison between Prokaryotic and Eukaryotic Cell:
|
Prokaryotic Cell |
Eukaryotic Cell |
Definition |
These are organisms made up of cells that lack a cell nucleus or any membrane-encased organelles. |
These organisms are made up of cells that possess a membrane-bound nucleus as well as membrane-bound organelles. |
Nucleus |
It has no nucleus. |
It has a true nucleus, bounded by a double membrane. |
DNA arrangement |
It has a circular loop. |
It is linear. |
Size |
Small cells ( < 5 µm) |
Large cells ( < 10 µm) |
Cell |
Always unicellular |
Mostly multi-cellular |
Cell wall |
Usually present; chemically complex in nature |
When present, chemically simple in nature |
Protein |
It does not contain protein in its DNA. |
It contains proteins in the DNA to form chromatin. |
Ribosome |
It contains small ribosomes. |
It contains large ribosomes. |
Cytoplasm |
No cytoskeleton |
Always have cytoskeleton |
Cell division |
Cell division is by binary fission |
Cell division is by mitosis |
Reproduction |
Reproduction is always asexual |
Reproduction is asexual or sexual |
Metabolic pathways |
Huge variety of metabolic pathways |
Common metabolic pathways |
Flagella |
Consist of two protein building blocks |
It is complex in nature and consists of multiple microtubules |
Multi-cellular forms |
Rare |
Common with extensive tissue formation |
Mesosomes |
They perform functions of golgi-bodies and mitochondria, and also help in separation of chromosomes. |
Not present |
Plasma membrane |
No carbohydrates and lacks sterols |
Sterols and carbohydrates are both present |
Glycocalyx |
Present as a capsule or slime layer |
Present in some cells which lack a cell wall |
Example |
Bacteria and Archaea |
Animal cells and plant cells |
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zoya
Mon, 02/19/2018 - 12:18
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