Protists vs Bacteria
According to common biological classification, protists are classified under Kingdom Protista, while Bacteria are classified under Kingdom Monera. Unlike the cells of other organisms (plants and animals), protists and bacteria cells have very low level of cell differentiation. Due to this reason, the cells of a single individual are morphologically and functionally similar, thus reduces its adaptations and development capacity.
Protists are considered as eukaryotes, basically due to the presence of nucleus of the cell, confined by a nuclear membrane. Most protists are unicellular and contain many organelles including membrane bounded organelles like mitochondria, chloroplast etc. Protists are classified under Kingdom Protista as they do not fit into the other kingdoms. Some protists actively ingest food into their cells, while others can make their own food by means of photosynthesis. Photosynthetic protists such as blue green algae are considered as vital primary producers in ecosystem. Protists can be divided into several groups based on the similarities to other higher kingdoms, including protozoa, protophyta, and slime moulds.
The Bacteria are considered as unicellular prokaryotic organisms. Unlike eukaryotes, bacteria cells lack an organized nucleus, mitochondria, chloroplasts and other membrane bounded organelles. Bacterial cell has only a circular DNA, which does not associate with histone protein. Bacteria do not show sexual reproduction methods. They reproduce asexually; mainly by binary fission under certain favorable conditions. Certain bacteria have flagella, which enables their locomotion. Bacterial cells vary in shape and occur single, in chains, or in clumps. The main types of shapes exits in bacteria are cocci, bacilli, vibrios, and spirilla.
What is the difference between Protists and Bacteria?
• Protists are classified under Kingdom Protista, while bacteria are classified under Kingdom Monera.
• Due to the presence of nuclear envelop, the protists cells are considered as eukaryotic cells, whereas bacteria cells are considered as prokaryotic cells as their cells lack nuclear envelop.
• Transcription and translation of bacteria occur in the same compartment while that of protists occur in different compartments.
• Unlike in bacteria, in protists, DNA are associated with histone proteins.
• Cytoskeleton is absent in bacteria, unlike in protists.
• Mitochondria may be present in protists, whereas bacteria cells lack mitochondria.
• Chloroplasts are absent in bacteria, while they are present in some forms of protists (photosynthetic protists).
• Mode of nutrition of bacteria is autotrophic or heterotrophic, whereas that of protists is photosynthetic or heterotrophic or combination of both.
• Unlike bacteria, certain primitive mechanisms have evolved for conducting stimuli in some forms of protists.