TYPE OF CELLS

Biotic components of the environment include all forms of life from minute bacteria to towering giant sequoias. But at the microscopic level, all living organisms are made up of the same basic unit cell. 

contents:

i) Prokaryotic cell

ii) Eukaryotic cell

iii) Different between Prokaryotic cell and Eukaryotic cell

1. Prokaryotic cells

The term "prokaryote"is derived from the Greek word "pro", (meaning:before) and "karyon"(meaning:kernel). It translates to "before nuclei."Prokaryotes are one of the most ancient groups of living organisms on earth, with fossil records dating back to almost 3.5 billion years ago.

Fig : Bacterial cell

• The Prokaryotic cells are represented by bacteria, blue-green algae, mycoplasma or PPLO (Pleuro Pneumonia Like Organisms). They are genereally sammaler and multiply more rapidly than the eukaryotic cells.
• The organisation of the prokaryotic cell is fundamentally similar even though prikaryotes exhibit a wide variety of shapes and functions.

2. Eukaryotic cell

The term "Eukaryotes" is derived from the Greek word "eu", (meaning:good) and "karyon" (meaning: kernel), therefore, translate to "good or true nuclei." Eukaryotes are more complex and much larger than the prokaryotes. They include almost all the major kingdoms except kingdom monera.

fig : Eukaryotic ( Animal cell)

• The eukaryotic include all the protists, plants, animals and fungi. In eukaryotic cells there is an extensive compartmentalisation of cytoplasm through the presence of membrane bound organelles.
• Eukaryotic cells possess an organised nucleus with a nuclear envelope. In addition, eukaryotic cells have a variety of complex locomotory and cytoskeletal structures. Their genetic material is organised into chromosomes.
• All eukaryotic cell are not identical. Plant and animal cells are different as the former possess cell walls, plastids and a large central vacuole which are absent in animal cells. On the other hand, animal cells have centrioles which are absent in almost all higher plant cells.

3. Different between Prokaryotic cell and Eukaryotic cell

Plant cells and animal cells are two types of eukaryotic cells. Thus, both these cell types are composed of membrane-bound organelles like nucleus, mitochondria and endoplasmic reticulum. Both cell types contain 80S ribosomes for protein synthesis. Plant cells exhibit a fixed, rectangular shape due to the presence of a cell wall. Their cell wall is mainly composed of cellulose. On the contrary, animal cells have a round, irregular shape due to the absence of a cell wall. The key difference between plant and animal cells is that plant cells are composed of cell walls and chloroplasts whereas animal cells lack cell walls and chloroplasts. 

fig : Plant cell

fig: Animal cell