differences between prokaryotic and eukaryotic cells

Prokaryotic cells:

• Unicellular
• Have a circular DNA form
• Have a flagella
• Small, simple cells measuring 0.5um

Eukaryotic cells:

• Multicellular
• Membrane bound organelles
• Have a nucleus
• Have a linear DNA form
• Large and complex, measuring 10-100um

Eukaryotic cells have a nucleus with DNA stored in it whilst prokaryotic don't have a nucleus and their DNA is freely floating inside the cytoplasm.

In cellular biology, prokaryotic and eukaryotic cells are the two basic classes, each with unique structural and functional characteristics. The way genetic material is organised is one of the main differences. Bacteria and archaea are examples of prokaryotic cells, which do not have a nucleus that is membrane-bound. Rather, their genetic material is found in a nucleoid region of the cell, where it is usually a single circular DNA molecule. In sharp contrast, eukaryotic cells have a distinct nucleus that is protected by a nuclear membrane. Within this specialised compartment, eukaryotic cells store their genetic material in many linear chromosomes.

Another obvious area where the two cell types differ is in size. Prokaryotic cells are usually smaller in size, measuring between 0.1 to 5 micrometres on average. On the other hand, eukaryotic cells range in size from 10 to 100 micrometres, making them relatively larger. Because bacterial cells lack the membrane-bound organelles that give eukaryotic cells their larger and more complex structure, it is commonly assumed that prokaryotic cells have a more streamlined structure.

When we take into account the existence of organelles, more differences become evident. Simple in their structure, prokaryotic cells do not have membrane-bound organelles. Even though key structures, such ribosomes, are present, they lack the protective membranes found in cells that are eukaryotic. Eukaryotic cells, on the other hand, have a variety of membrane-bound organelles, each of which performs a specific role. These include the Golgi apparatus, lysosomes, mitochondria, and endoplasmic reticulum, which all contribute to the eukaryotic cells' complexity.

Binary fission is a quick and easy type of asexual reproduction used by prokaryotic bacteria. But eukaryotic cells go through meiosis when they generate gametes and mitosis during somatic cell division, which helps with both sexual and asexual reproduction. Understanding cellular diversity in the biological world is based on these differences between prokaryotic and eukaryotic cells, which are characterised by differences in size, shape, organelles, and reproductive mechanisms.

Eukaryotic cells contain their DNA in a nucleus and have membrane bound organelles such as the smooth and rough endoplasmic reticulum, golgi apparatus, and lysosome. However, prokaryotic cells contain their DNA in the form of circular DNA free in the cytoplasm and also have DNA in plasmids, which are circular.

Prokaryotic cells are older, and much smaller than Eukaryotic cells. However, the main difference between these two cells is that Eukaryotic have a membrane bound nucleus, whereas prokaryotic cell's DNA is free floating within the cytoplasm.

The main difference between eukaryotic and prokaryotic cells is that eukaryotic cells contain membrane bound organelles whilst prokaryotes do not. Another main difference is that eukaryotes have their DNA enclosed in a nucleus whilst the DNA of prokaryotes are found free in the cytoplasm and can sometimes be found in the form of plasmids.

Prokaryotes are unicellular organisms that lack membrane-bound structures, the most noteworthy of which is the nucleus. Prokaryotic cells tend to be small, simple cells, measuring around 0.1-5 μm in diameter.  

The main difference between prokaryotic and eukaryotic cells is that eukaryotic cells have membrane-bound organelles, meaning that their sub cellular components such as the mitochondria, and most importantly the nucleus (where the DNA is kept) are surrounded by an extra layer of protection known as a membrane.

In prokaryotic cells, all sub cellular structures are floating around in the cytoplasm, even the DNA; though the DNA is coiled up and mostly floats in an area of the cell known as the nucleoid.

There are some other major differences, such as prokaryotic are really small in comparison to eukaryotes, their chromosomes are circular and short, where as eukaryotes have linear and longer chromosomes and the type of ribosomes that they have are also different.

Eukaryotic - a nucleus

Prokaryotic - a free-floating strand of DNA

Eukaryotic - large ribosomes

Prokaryotic - smaller ribosomes

Prokaryotic - no mitochondria

Eukaryotic - mitochondria

Prokaryotic and eukaryotic cells are the two primary types of cells, differing fundamentally in their structure and complexity. Here are the key differences between them:

1. Nucleus:

• Prokaryotic cells lack a true nucleus. Their genetic material is not enclosed within a nuclear membrane; instead, it is located in a region called the nucleoid.
• Eukaryotic cells have a well-defined nucleus, where the cell’s DNA is enclosed within a nuclear envelope.

1. Cell Size:

• Prokaryotic cells are generally smaller, typically between 0.1 to 5 micrometers in diameter.
• Eukaryotic cells are larger, usually between 10 to 100 micrometers in diameter.

1. Cell Complexity:

• Prokaryotic cells are simpler in structure, with fewer types of organelles.
• Eukaryotic cells are more complex, containing a variety of organelles such as mitochondria, the endoplasmic reticulum, and the Golgi apparatus.

1. Cell Wall:

• Many prokaryotes have a rigid cell wall composed of peptidoglycan (in bacteria) or other substances.
• Eukaryotic cells may or may not have a cell wall. If present, the cell wall is usually made of cellulose (in plants) or chitin (in fungi).

1. Ribosomes:

• Prokaryotic cells contain 70S ribosomes, which are smaller.
• Eukaryotic cells contain 80S ribosomes, which are larger.

1. DNA Structure:

• Prokaryotic DNA is typically circular and not associated with histone proteins.
• Eukaryotic DNA is linear and closely associated with histones to form chromatin and chromosomes.

1. Reproduction:

• Prokaryotes reproduce asexually through processes such as binary fission.
• Eukaryotes can reproduce both sexually and asexually, with mechanisms including mitosis and meiosis.

1. Organelles:

• Prokaryotic cells lack membrane-bound organelles.
• Eukaryotic cells have multiple membrane-bound organelles, such as mitochondria, chloroplasts (in plants), the endoplasmic reticulum, and the Golgi apparatus.

1. Cytoplasmic Division:

• Prokaryotic cells often divide by binary fission, where the cell simply splits into two.
• Eukaryotic cells divide by mitosis or meiosis, involving complex processes of chromosomal alignment and separation.

1. Genetic Recombination:

• Prokaryotic genetic recombination occurs through processes such as transformation, transduction, and conjugation.
• Eukaryotic genetic recombination primarily occurs during meiosis.

These differences reflect the evolutionary distance between prokaryotic and eukaryotic organisms, with eukaryotic cells representing a more complex and compartmentalized cellular organization.

Similarities:

1. Cell Membrane: Both prokaryotic and eukaryotic cells have a cell membrane.

2. Genetic Material: They both contain genetic material (DNA)

Differences:

1. Nucleus: Prokaryotic cells lack a nucleus, while eukaryotic cells have a nucleus.

2. Membrane-bound Organelles: Eukaryotic cells possess membrane-bound organelles like mitochondria, which are absent in prokaryotic cells.

3. Cell Size: Prokaryotic cells are generally smaller, while eukaryotic cells can be larger and more complex.

4. DNA Structure: Prokaryotic cells have a single circular DNA molecule, while eukaryotic cells have multiple linear DNA molecules forming chromosomes.

Nucleus:

• Prokaryotic cells: Lack a true nucleus. Instead, their genetic material is typically found in a region called the nucleoid, which is not enclosed by a membrane.
• Eukaryotic cells: Have a well-defined nucleus enclosed within a double membrane, which contains the cell's genetic material in the form of chromosomes.

Membrane-bound Organelles:

• Prokaryotic cells: Generally lack membrane-bound organelles. They may have some internal structures like ribosomes, but these are not enclosed by membranes.
• Eukaryotic cells: Contain membrane-bound organelles such as mitochondria, endoplasmic reticulum, Golgi apparatus, lysosomes, and chloroplasts (in plant cells). These organelles perform specialized functions within the cell.

Size:

• Prokaryotic cells: Typically smaller and simpler in structure compared to eukaryotic cells.
• Eukaryotic cells: Generally larger and more complex in structure due to the presence of membrane-bound organelles and a well-defined nucleus.

Cell Wall:

• Prokaryotic cells: Most prokaryotic cells have a cell wall, which provides structural support and protection. The composition of the cell wall varies among different types of prokaryotes (e.g., bacteria have a peptidoglycan cell wall).
• Eukaryotic cells: Some eukaryotic cells, such as plant cells and fungal cells, have a cell wall composed of materials like cellulose or chitin. Animal cells do not have a cell wall.

Reproduction:

• Prokaryotic cells: Reproduce primarily through binary fission, a process in which the cell divides into two identical daughter cells.
• Eukaryotic cells: Reproduce through mitosis (for somatic cells) or meiosis (for reproductive cells), processes that involve the division and distribution of chromosomes to daughter cells.

Genetic Material:

• Prokaryotic cells: Typically have a single circular chromosome composed of DNA. They may also contain small, circular pieces of DNA called plasmids.
• Eukaryotic cells: Have multiple linear chromosomes composed of DNA, which are located within the nucleus. Eukaryotic cells may also contain extranuclear DNA in organelles such as mitochondria and chloroplasts.

Prokaryotic cells do not have a nucleus, whereas, a eukaryotic cell does.

Prokaryotic cells are typically smaller, whereas, a eukaryotic cell is larger.

Prokaryotic cells contain only singular chromosomes, whereas, a eukaryotic cell can contain more than one.

Prokaryotic cells do not have certain organelles such as mitochondria or chloroplast, whereas, a eukaryotic cell can.

The biggest difference is that a eukaryotic cell (plant/animal/fungus) cell has a nucleus, whereas a prokaryotic (bacterial) cell does not. Prokaryotic genetic material floats freely in the cell cytoplasm.

Aside from that, here are some other key differences:

• Edivide by mitosis (meiosis in gametes), prokaryotes divide by binary fission
• Eukaryotes are 5μm - 100μm, prokaryotes are much smaller (0.2-2μm)
• Prokaryotes don't contain mitochondria or chloroplasts
• 
  

Key differences between prokaryotic cells and eukaryotic cells are:

The cells are much smaller.

No membrane bound-organelles

Smaller ribosomes

No nucleus

A cell wall made of murein