Are you familiar with a cell’s internal structure? How many different cell kinds are there? And what distinguishes them?
Are you interested in learning more about the differences between prokaryotes and eukaryotes? Let’s have a look at it together!!
The cell is the basic unit and the foundation of life. It is sometimes called “a small room,” of life’s functional and structural unit.
It is a little unified space where a variety of actions and reactions occur simultaneously.
Single-celled organisms, sometimes known as unicellular organisms, possess only one cell. Multicellular creatures, on the other hand, are made up of many cells.
In 1665, Robert Hook was the first to discover the cell. Organelles that are membrane-bound are found in certain cells but not in others. In an organism, there exist two types of cells: Eukaryotic and Prokaryotic.
Any of these cells may exist depending on the internal composition of the cell. What are the differences between prokaryotic and eukaryotic cells?
What Are Prokaryotic Cells?
Morphologically, this type of cell is considered the most primordial cell. It naturally does not have a distinct nucleus and the chromatin bodies are dispersed throughout the cytoplasm.
Organisms like bacteria and cyanobacteria (blue-green algae) are examples of prokaryotes. Organisms with prokaryotes rely on asexual division for binary fission (reproduction).
Prokaryotic cells are small, basic cells that range in size from 0.1 to 5 micrometers in diameter.
Key Features of Prokaryotic Cells
- Nucleoid: The nucleoid is the core part of the cell that houses the cell’s DNA.
- Ribosome: Ribosomes are responsible for carrying out protein synthesis.
- Capsule: In some bacteria, the capsule is a covering of carbohydrates that surrounds the cell wall. Because of the capsule, bacteria may adhere to surfaces.
- Cell wall: The cell wall gives the cell structure and protects it from the outside world. Peptidoglycans are a form of cell wall composed of carbohydrates and proteins found in most bacteria.
- Cell membrane: In every prokaryote, the cell membrane, also known as the plasma membrane, separates the cell from the external environment.
- Fimbriae: These are little, hair-like structures that aid in cellular adhesion.
- Pili: Pili are rod-shaped structures responsible for a variety of activities, including DNA transfer and attachment.
- Flagella are little, tail-like structures that help in movement.
What Are Eukaryotic Cells?
Prokaryotes are believed to have evolved into eukaryotes. They have a distinct nucleus and a nuclear membrane that surrounds the chromatin bodies.
Eukaryotes are found in the cytoplasm, and they contain organelles such as mitochondria that are separated by membranes.
Plants and animals are examples of eukaryotic living organisms. They exhibit both asexual and sexual division.
They are larger than prokaryotes, and they possess superior structural organization and functional efficiency.
Eukaryotic cells are huge and complicated, with lengths ranging from 5 to 100 micrometers. While many eukaryotes are multicellular organisms, some are single-cell organisms.
Key Features of Eukaryotic Cell
- Nucleus: The nucleus houses genetic information in the form of chromatin.
- Nucleolus: The nucleolus is a component of eukaryotic cells that produce ribosomal RNA and is found inside the nucleus.
- Plasma membrane: The plasma membrane is a phospholipid bilayer that encases and covers the cell’s organelles.
- Cytoskeleton: Often known as the cell wall, provides structure, allows for cell movement, and aids in cell division.
- Ribosomes: Protein synthesis is carried out by ribosomes.
- Mitochondria: The mitochondria are usually called the cell’s powerhouses, and are responsible for energy production.
- Cytoplasm: the portion of the cell between the nuclear envelope and the plasma membrane.
- Cytosol: The cytosol is a gel-like particle that contains the organelles within the cell.
- Endoplasmic reticulum: The endoplasmic reticulum is an organelle that is responsible for protein maturation and trafficking.
- Vesicles and vacuoles: These are membrane-bound sacs that play a role in transit and storage.
Comparing Prokaryotes and Eukaryotes
Eukaryotic cells possess a membrane-bound nucleus, whiles prokaryotic cells do not. Eukaryotes keep their genetic information in the nucleus.
In eukaryotes, the nucleus is one of the numerous membrane-bound organelles. On the other hand, prokaryotes, do not have organelles that are attached to the membrane.
DNA is bundled in the nucleoid area of prokaryotes, but it is not kept in a membrane-bound nucleus. Another significant distinction is the DNA structure.
Prokaryotic DNA is double-stranded and circular, whereas eukaryotic DNA is made up of several molecules of double-stranded linear DNA.
Difference Between Prokaryotes and Eukaryotes
Prokaryotes and eukaryotes differ in several ways, including structural distinctions such as whether the cell has a nucleus and whether it has membrane-bound organelles, as well as molecular differences such as whether the DNA is circular or linear.
The table below summarizes the differences between these two types of cells.
Prokaryote | Eukaryote | |
---|---|---|
Nucleus | Absent | Present |
Membrane-bound organelles | Absent | Present |
Cell structure | Unicellular | Mostly multicellular; some unicellular |
Cell size | Smaller (0.1-5 μm) | Larger (10-100 μm) |
Complexity | Simpler | More complex |
DNA Form | Circular | Linear |
Chromosome | One chromosome is present, but not true chromosome plastids | More than one number of chromosomes is present. |
Lysosomes and Peroxisomes | Absent | Present |
Microtubules | Absent | Present |
Endoplasmic reticulum | Absent | Present |
Mitochondria | Absent | Present |
Cytoskeleton | Absent | Present |
Ribosomes | Smaller | Larger |
Chloroplasts | Chloroplasts absent; chlorophyll scattered in the cytoplasm | Chloroplasts present in plants |
Reproduction | Asexual reproduction | Sexual and Asexual reproduction |
Vacuoles | Absent | Present |
Nuclear membrane | Permeability of nuclear membrane is not present | Permeability of nuclear membrane is selective |
Examples of Organisms | Bacteria and Archaea | Protists, Fungi, Plants, and Animals |
Key Similarities Between Prokaryotes and Eukaryotes
These four characteristics are shared by all cells, whether prokaryotic or eukaryotic:
- DNA
- Plasma membrane
- Cytoplasm
- Ribosomes