Salient features of the Kingdom Monera: Definition, Characteristics and Structure
Salient features of the Kingdom Monera: Definition, Characteristics and Structure
Edited By Irshad Anwar | Updated on Jun 08, 2025 10:33 AM IST
The term monera refers to a broad class of simple, single-celled organisms, such as bacteria, cyanobacteria, and archaea. These are prokaryotic because they don't have a true nucleus. They are very important in nature because they recycle nutrients, create symbiotic relationships with other living things, and even act as early producers in ecosystems.
This Story also Contains
Kingdom Monera
Salient Features of Kingdom Monera
Examples of Monera
Recommended video on "Characteristics of Kingdom Monera":
Salient features of the Kingdom Monera: Definition, Characteristics and Structure
In a number of domains, including biotechnology, agriculture, and medicine, monerans can also be advantageous to humans. Because of their ability to reproduce quickly, survive in varied environments, and adapt genetically makes them key to understanding how microorganisms support life on Earth. Being one of the oldest and most diverse life forms, they teach us about early life and how ecosystems function. Kingdom Monera is an important chapter of the subject of Biology.
The Kingdom Monera includes a vast array of organisms. All of these organisms are prokaryotic in their cellular structure, meaning that their cells lack membrane-bound organelles and do not have a nucleus. These primarily comprise bacteria and cyanobacteria. Members can be found widely distributed in almost every environment on Earth, from deep-sea vents to the human intestines. Because they lack complexity, their very important ecological roles are often overlooked. They provide nutrient cycling, as well as participate in biogeochemical processes. The research on Monera provides knowledge of the general principles of cellular biology and microbiology. At the same time, it helps elaborate upon the evolutionary perspective and practical use of the Monera in biotechnology to medicine.
Bacteria can be classified into four major types based on their shape:
Coccus – Spherical shaped
Bacillus – Rod-shaped
Vibrium – Comma-shaped
Spirillum – Spiral-shaped
NEET Highest Scoring Chapters & Topics
Know Most Scoring Concepts in NEET 2024 Based on Previous Year Analysis.
The following points highlight the major characteristics of organisms belonging to the Kingdom Monera. These features cover their structure, function, reproduction, and nutrition.
1. Prokaryotic Organisms: All Monerans are prokaryotes, meaning they lack a true nucleus and membrane-bound organelles.
2. Unicellular: They are single-celled organisms, but some may form colonies or chains (like in cyanobacteria).
3. Cell Wall: Most have a rigid cell wall made of peptidoglycan (in bacteria), which gives shape and protection.
4. No Membrane-Bound Organelles: Organelles like mitochondria, ER, and Golgi bodies are absent; cellular functions occur in the cytoplasm.
5. Genetic Material: DNA is present in a single, circular chromosome located in a region called the nucleoid; small DNA rings called plasmids may also be present.
6. Reproduction: They mostly reproduce asexually by binary fission. Some show gene transfer through conjugation, transformation, or transduction.
7. Nutrition Types: Monerans show diverse modes of nutrition:
Autotrophic (e.g., cyanobacteria) – can photosynthesize
Heterotrophic – includes saprophytic, parasitic, and symbiotic types
Chemosynthetic autotrophs – obtain energy from inorganic chemicals
8. Respiration: Can be aerobic (needs oxygen) or anaerobic (does not need oxygen).
9. Mobility: Many bacteria move using flagella, while others are non-motile.
10. Cyanobacteria: Also called blue-green algae, these are photosynthetic and contain chlorophyll similar to plants.
11. Archaea: These are ancient bacteria that live in extreme conditions like high salt (halophiles), hot springs (thermoacidophiles), or produce methane (methanogens).
12. Metabolism: Monerans have varied metabolism and can survive in diverse and even extreme environments.
13. Shape-Based Classification: Bacteria come in various shapes – coccus (spherical), bacillus (rod-shaped), spirillum (spiral), and vibrio (comma-shaped).
14. Economic Importance: Some bacteria are helpful in nitrogen fixation, fermentation, and biotechnology; others can cause diseases.
15, Rapid Growth: Under suitable conditions, bacteria can multiply rapidly, making them successful colonisers.
Examples of Monera
Here are some common examples of Monera, which include various types of bacteria and other prokaryotic organisms.
Eubacteria (True Bacteria)
The following points describe Eubacteria, also known as true bacteria, which are found in almost every environment and show a wide range of metabolic activities.
They are the largest and the most varied of the Kingdom Monera.
They have cell walls composed of peptidoglycan, and their metabolic ability ranges from photosynthesis to fermentation.
They live symbiotically with plants and animals and, in a free-living state, occupy many different ecosystems.
Archaebacteria (Ancient Bacteria)
These are ancient bacteria that live in extreme environments. The following lines explain their features and types based on habitat.
The archaea are unrelated to eubacteria, and many archaea live in extreme environments like hot springs, salty lakes, and deep-sea hydrothermal vents.
They have unique cell membrane lipids and different ribosomal proteins from all other organisms.
Archaea also hold critical clues to Earth's early environmental conditions and to the evolution itself.
Cyanobacteria (Prokaryotic, Blue-Green Algae)
Cyanobacteria are photosynthetic Monerans, also known as blue-green algae. The points below explain their structure and ecological role.
These are photosynthetic bacteria that generate oxygen as they carry out photosynthesis.
Hence, ecologically, they play a vital role in the aquatic environment as primary producers and also fix nitrogen in some species.
These groups together cause harmful algal blooms in nutrient-rich waters.
Mycoplasma (Wall-less Monerans)
Mycoplasmas are the smallest and simplest living cells without a cell wall. Here are a few key features about them.
What makes Mycoplasma unique among bacteria is that they do not have a cell wall; as a result, they are considered pleomorphic.
They are parasites or commensals and often infect plants and animals and cause diseases in human beings, like pneumonia.
Species of the genus Mycoplasma have some of the smallest genomes among free-living organisms, reflecting their adaptation to parasitic lifestyles.
Recommended video on "Characteristics of Kingdom Monera":
Frequently Asked Questions (FAQs)
1.What are the main characteristics of Kingdom Monera?
Kingdom Monera consists of prokaryotic organisms that do not have membrane-bound organelles and also include bacteria and cyanobacteria.
2.How do bacteria reproduce?
Bacteria essentially exhibit a mode of reproduction by binary fission, where one cell is simply divided into two identical daughter cells.
3.What is the role of bacteria in the environment?
In the context of ecosystems, bacteria play some of the most critical roles in nutrient cycling, decomposition of organic matter, and symbiosis with other organisms.
4.What are the different types of bacterial metabolism?
The metabolism of bacteria can be autotrophic- mostly photosynthetic or chemosynthetic-and heterotrophic, where it provides energy through various biochemical pathways of producing energy.
5.How are antibiotics related to bacteria?
Antibiotics attack specific structures or processes of bacteria; they interfere with bacterial growth so that bacterial infections can be treated.
.jpg)