15 Difference Between Bacterial Cell and Human Cell

The differences between bacterial cells and human cells are few but quite significant.

Difference Between Bacterial Cell and Human Cell
Bacterial cell structure vs human cell

Difference Between Bacterial Cell and Human Cell

Differences Bacterial cell Human cell
Cell survivesIndependently
It survives on its own and is isolated.
Human cells exist in group.
One is dependent on the other cells for survival.
Cell wallA thick protective cell wall is present, covering the whole cell.The cell wall is absent.
The cell membrane is made ofIt is made of a phospholipid bilayer without cholesterol.

Have, instead, hopanoids.
A prominent and distinct nucleus is present within the nuclear membrane.
Hence, are called eukaryotes.
Cytoplasmic bridges (intercellular bridges)There are no cytoplasmic bridges (as they are individual cells).Cytoplasmic bridges are present in male and female germ cells.

These facilitate the sharing of nutrients and inter-cellular transport between neighboring cells.
Cell shapesCells can be of different shapes, like Spherical
Comma
Rod-shaped
chains
spiral.
few like
spherical, oval,
cubical.
Cell appendages (External attachments)Present.
Flagella for movement,
Pili for sexual reproduction.
Absent mostly.
Except for cilia in the respiratory tract & gut.
NucleusThe nucleus is Absent.
Instead, nuclear content like DNA is present in the cytoplasm.
Hence, called prokaryotes
A prominent and distinct nucleus is present with the nuclear membrane.
Hence, they are called eukaryotes.
Membraned cell organellesAbsentPresent like mitochondria, golgi apparatus, endoplasmic reticulum, lysosomes.
Chromosome (DNA) structureHave a single circular chromosome and plasmids, which are circular DNA molecules.Have multiple linear chromosomes.
PlasmidsPresentAbsent
DNA synthesis differencesEnzyme DNA Gyrase is involved.Enzyme Topoisomerase is involved
Ribosomes70s type ribosome with the 50s and 30s subunits.80s type ribosome with the 60s and 40s subunits.
Capsule (a form of an inactive cell)The bacterial cell transforms into a capsule during harsh conditions of drought and temperature.
It can give back live bacteria in good condition.
Capsule formation is Absent
Aging and Cell deathThe bacterial cell is considered immortal.
It never dies unless subjected to sterilization or attack by immune cells, etc.
Divides for new offspring. Even in harsh conditions, it tries to survive as spore form (dormant)
The human cell is mortal.
The cell dies by either aging, apoptosis, or necrosis.
Nutrition habitsHave Different types
Autotrophic,
heterotrophic,
parasitic, etc.
๐Ÿ‘‰ Autotrophs manufacture their own food.
๐Ÿ‘‰ Disease-causing bacteria are parasites & live on other organisms.
Heterotrophs.
๐Ÿ‘‰ Depends on the food supplied from other sources, such as blood from the body’s gut.
ReproductionAsexual.
Bacteria undergo asexual reproduction by binary fission.
They can also go for genetic exchange, similar to sexual reproduction.
Sexual reproduction by gamet fusion.
Cells multiply by mitosis.
Cell division occurs byMitosis and meiosis.

1. Mitosis gives 2 cells.

2. Meiosis gives 4 cells
1. Most cells undergo mitosis.

2. Ovum and sperm form by meiosis.
3. Nerve cells never divide.
MovementThey can move on their own with flagella for normal needs.They cannot move except for sperm and ova.
Similarly, blood cells flow in the circulation process.
SizeSmaller (0.2โ€“2.0 ยตm)Larger (10โ€“100 ยตm)
ExamplesE.coli, PseudomonasNerve cell, muscle cell.

Before you go into details, kindly check the details on the cell and its organelles.

  • Also, there are variations, such as bacteria being immortal creatures, i.e., they do not die as such except under harsh conditions.
  • They are quite primitive living organisms on the Earth and are of various types.
  • On the other hand, a human is an advanced living being.

As you have heard before, some of them cause various diseases in humans, while others are also human-friendly.

They are single-celled organisms, and yet that single cell can perform all of its functions.

These differences are the key to the treatment of bacterial diseases by the use of antibiotics.

Bacteria cell with different cell components.
A bacterial cell with cell components like chromosomes, pilus, flagella, ribosomes, plasmids, etc.

Targeting and killing bacterial cells without such differences would be difficult once they enter the human body.

Human cell diagram with labelled parts
  • The difference between bacterial and human cells helps us fight bacterial infections.
  • When administered into the human body, antibiotics act so that only bacterial cells are killed while sparing humans.
  • The common targets to achieve this safe drug action are the cell wall, 70s ribosomes, DNA gyrase, etc.

Ex: Penicillins kill bacteria by acting on their cell wall.

  • Since the human cell lacks a cell wall, human cells are unaffected by it.
  • Similarly, streptomycin acts only on 70s ribosomes and prevents their protein synthesis, while there are 80s ribosomes in human cells.
  • So they are not affected by the antibiotics.

Also, see the Differences between the cell membrane & Cell Wall.

  • Besides, the translation of a process involved in forming a new protein from mRNA is entirely different in bacteria.
  • In humans, the mRNA formed by transcription comes out of the nucleus and is then translated on the rough endoplasmic reticulum.
  • But in bacteria, there is no nuclear membrane.
  • So, the formation of mRNA and protein synthesis happens almost simultaneously.

References:

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