xix.2. Types of Cell

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xix.2. Types of Cell

Cells and thus organisms can be categorized as eukaryotic or prokaryotic depending on whether they include or lack a membrane-bound nucleus and other organelles.

Prokaryotic Cells

Prokaryotic cells are single-celled microorganisms that are thought to be the oldest on the planet.
Bacteria, blue-green algae, mycoplasma, and PPLO (Pleuro Pneumonia Like Organisms) are examples of prokaryotic cells.
They typically have a smaller size and reproduce more quickly.
They could have a wide range of sizes and shapes.
With the exception of mycoplasma, prokaryotes have a cell wall that surrounds the cell membrane.
A prokaryotic cell has a single membrane, all reactions take place in the cytoplasm.
No distinct nucleus is present.
The genetic material is essentially naked because it is not surrounded by a nuclear membrane.
The genetic material is contained on a single chromosome.
Lysosomes, chloroplasts, Golgi bodies, and mitochondria are not present.
Ribosomes are connected to the cell’s plasma membrane in prokaryotes. Ribosomes responsible for protein synthesis
The cell wall determines the shape of the cell and provides strong structural support to prokaryotes. And to prevent the bacterium from bursting or collapsing.
Prokaryotes are distinguished by a specific type of differentiated cell membrane called a mesosome. In essence, they are infoldings of the cell membranes.
The term “capsule” refers to the outer protective layer that bacteria have in addition to their cell walls. It aids in the retention of moisture, guards against cell engulfment, and aids in the clinging of cells to surfaces and nutrients.
Prokaryotic cells store extra material as inclusion bodies in the cytoplasm. Phosphate granules, cyanophycean granules, and glycogen granules are a few examples of those that are not bound by any membrane systems and are found floating freely in the cytoplasm.
They reproduce asexually through binary fission.
Further membrane expansions into the cytoplasm called chromatophores, which contain pigments, are seen in some prokaryotes such as cyanobacteria.
Prokaryotic cells are those without a membrane-bound nucleus.

Eukaryotic Cells

Eukaryotic cells have a well-organized nucleus surrounded by a nuclear envelope.
Protists, plants, animals, and fungi are all considered to be eukaryotes.
The existence of membrane-bound organelles results in considerable compartmentalization of cytoplasm in eukaryotic cells.
Eukaryotic cells feature a wide range of intricate cytoskeletal and locomotory structures.
The genetic material in their bodies is organized into chromosomes.
Not every eukaryotic cell is the same. Plant cells differ from animal cells in that they have a cellwall, plastids, and a huge central vacuole, which are all absent in animal cells.
They can reproduce asexually or sexually.
A process known as mitosis divides the cells.