What Makes Bacteria Unique in the World of Biology?
Bacteria are the minute living organisms, which are found abundantly on the planet earth. It is also recognised as one of the earliest forms of life, which existed on the earth. They were the very earliest organisms to evolve on this planet earth, i.e. it was over 2 billion years before eukaryotes appeared.
Bacteria are a giant group of minute, unicellular living organisms, which are also called microbes or microorganisms. These microscopic organisms are called prokaryotes as they lack a true nucleus and other cellular organelles.
The bacterium is the singular word for bacteria. The study of bacteria is known as bacteriology and it is a branch of Microbiology. Bacteria were first observed by the Dutch microscopist Antonie van Leeuwenhoek in 1675.
Characteristics Of Bacteria
Bacteria mainly comprises a simple cellular structure, including:
Capsule
Cell wall
Flagellum
Pili
Cytoplasm
Ribosomes
Chromosomes.
These microorganisms are found everywhere, all around us and are found in communities of millions. The shape of bacteria varies with the types and the length of a complete bacteria measures only a few micrometres.
Other Structural Features of These Prokaryotic Microorganisms are:
It lacks a membrane-bound nucleus.
It has a circular shaped, single chromosome of DNA found within the cytoplasm.
The nucleoid of a bacterial cell comprises the chromosome with its associated proteins and RNA.
Every bacterial cell has its own plasmids, which are involved in replication, food digestion, etc.
These plasmids are small, circular, double-stranded DNA Structure, which are naturally found in all bacterial cells.
The mode of reproduction process in bacteria is both through sexual and asexual methods. Most bacteria rely on binary fission.
There are Several different Types of Bacteria and the Classification of Bacteria are Mainly Based on Their:
Mode of Respiration: Aerobic or Anaerobic.
Nutritional Patterns: Autotrophic or heterotrophic.
Reproduction: Binary fission, conjugation, transduction and transformation.
Shapes: Bacillus, Coccus, spirillum or spirochete and Vibrio.
Cell Wall Composition: Gram-positive and Gram-negative.
Interesting Facts about Bacteria
Fact- No-1
Bacteria play a primary role in regulating biogeochemical systems.
Fact- No-2
These bacteria also protect our body from defending the invading pathogens.
Fact- No-3
The smell of rain is also caused by a certain group of gram-positive bacteria present in the soil.
Fact- No-4
Compared to the other human body parts, mouth and belly buttons have more than a thousand to millions of new species of bacteria.
Fact- No-5
Bacteria act as biocontrol agents and also act as cleaning and disinfectant agents.
Fact- No-6
These bacteria are both beneficial and harmful for humans, animals and also for plants.
Fact- No-7
Bacteria are present both outside the body and deep inside in our gut which helps indigestion.
Fact- No-8
Bacteria occur in different shapes and sizes – sphere, rod, spiral and spherical shape.
Fact- No-9
There are many bacteria present in our gut which helps in digestion and protects our body from defending the invading pathogens.
Fact- No-10
Bacteria form a crucial part of the ecosystem, which takes part in activities like production of gases like oxygen, carbon dioxide and nitrogen and minerals like nitrogen, sulphur, etc.
Fact- No-11
There are various applications of bacteria, which includes food and beverage industries, the pharmaceutical industry, in the production of biofuel, biopesticides and so on.
Fact- No-12
A human body has 10 times more bacterial cells than human cells. These bacteria may either be a good bacteria or a pathogen- disease-causing bacteria like various bacterial infections and other fatal diseases.
Fact- No-13
Similar to other animals and birds, bacteria also communicate with each other by sending electrical signals. In this way, a colony of bacterial cells communicates and works together.
Fact- No-14
Actinomycetes are Gram-positive, mycelial, soil bacteria, which are more beneficial to humans. They are a great source of antibiotics and are also used in the production of a wide variety of chemotherapeutics, fungicides, herbicides and other industrially relevant compounds.
Fact- No-15
According to WHO and other medical records, one-third of the total world’s population has been infected with a dangerous and highly contagious bacterial disease called TB-Tuberculosis.
FAQs on Essential Facts About Bacteria
1. What are bacteria?
Bacteria are microscopic, single-celled organisms that are considered one of the earliest forms of life on Earth. They are classified as prokaryotes because their cells do not have a true nucleus or other membrane-bound organelles like the cells of plants and animals. Bacteria are found in almost every habitat on the planet.
2. What are some interesting facts about bacteria?
Some interesting facts about bacteria include:
The human body contains about 10 times more bacterial cells than human cells, many of which are essential for health.
Bacteria have been found living in extreme environments, such as boiling hot springs, deep-sea volcanic vents, and even in radioactive waste.
Some bacteria, like cyanobacteria, produce a significant amount of the Earth's oxygen through photosynthesis.
Bacteria can communicate with each other using a process called quorum sensing, allowing them to coordinate their behaviour.
3. Are all bacteria harmful to humans?
No, not all bacteria are harmful. In fact, the vast majority are harmless or even beneficial. Pathogenic bacteria, like Salmonella or Streptococcus, can cause diseases. However, beneficial bacteria, such as Lactobacillus used in making yoghurt and cheese, and the bacteria in our gut that help with digestion, are essential for both industry and human health.
4. What are the main types of bacteria based on their shape?
Bacteria are commonly classified into four main types based on their basic shapes:
Cocci: Spherical or ball-shaped bacteria.
Bacilli: Rod-shaped bacteria.
Spirilla: Spiral or corkscrew-shaped bacteria.
Vibrio: Comma-shaped bacteria.
5. What is the importance of bacteria in the environment?
Bacteria play a crucial role in the environment as primary decomposers. They break down dead organic matter, recycling essential nutrients like carbon and nitrogen back into the ecosystem for plants to use. Some bacteria are also capable of nitrogen fixation, converting atmospheric nitrogen into a form that can be used by living organisms, which is a vital process for all life on Earth.
6. What is the key difference between a bacterial cell and a plant or animal cell?
The most fundamental difference is that a bacterial cell is prokaryotic, while plant and animal cells are eukaryotic. This means a bacterial cell lacks a membrane-bound nucleus; its genetic material (DNA) floats in the cytoplasm in a region called the nucleoid. Eukaryotic cells, on the other hand, have a true nucleus that contains their DNA, as well as other complex, membrane-bound organelles like mitochondria and the endoplasmic reticulum.
7. How do bacteria reproduce so quickly?
Bacteria reproduce primarily through a process called binary fission. This is a form of asexual reproduction where a single bacterial cell grows to double its size and then splits into two identical daughter cells. This process is extremely rapid; under ideal conditions, some bacteria like E. coli can divide every 20 minutes, leading to exponential growth in their population.
8. Why are some bacteria becoming resistant to antibiotics?
Bacteria can become resistant to antibiotics through natural selection. Within a large bacterial population, some individuals may have random mutations in their DNA that make them naturally resistant to an antibiotic. When that antibiotic is used, it kills the susceptible bacteria but leaves the resistant ones to survive and multiply. The overuse and misuse of antibiotics accelerate this process, leading to the spread of antibiotic-resistant strains, which pose a significant threat to public health.
