Prokaryotes

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About Prokaryotes:

They are single-celled organisms that lack a distinct nucleus and other membrane-bound organelles.
Features
- Shape: They come in various shapes and sizes (0.5-5 µm), with four basic shapes being rod-like (bacillus), spherical (coccus), comma-shaped (vibrio), and spiral (spirillum).
- Cell organisation: Prokaryotic cells have a basic structural organisation, which includes a cell wall (except in mycoplasma), cytoplasm, and a plasma membrane. However, they lack a well-defined nucleus.
- Organelles: They lack membrane-bound organelles, except for ribosomes.
- They do have unique structures called mesosomes, which are extensions of the plasma membrane used for various functions.
- Reproduction: Prokaryotic cells reproduce primarily through binary fission, a type of asexual reproduction.
- DNA: Most prokaryotic cells have a single chromosome, which carries hereditary genes in the form of DNA.
Prokaryotes include bacteria and “archaea”, another type of single-celled organism.
These organisms are thought to be the oldest cell-based lifeforms on Earth.
Habitat: They thrive across the entire planet – on land and in water, from the tropics to the poles.
Ecological significance: They play a crucial role in the world’s food chains, helping support the nutrient needs of fish humans catch and eat.

Marine prokaryotes grow extremely fast – a process that emits a lot of carbon.

Q1: What are Eukaryotic Cells?

Eukaryotic cells are found in multi-cellular organisms such as protists, plants, animals, and fungi. They are more complex as compared to prokaryotic cells.

Source: Earth’s oldest, tiniest creatures are poised to be climate change winners