Kingdom Monera Features Practice Questions
40 free Kingdom Monera Features practice questions for the NCERT Biology. Tap an option to answer — you get instant feedback, the correct answer, and a detailed explanation for every question.
Which organisms are considered the sole members of Kingdom Monera?
- A Fungi
- B Protozoans
- C Bacteria
- D Slime moulds
Correct answer: Bacteria
Bacteria are the most abundant micro-organisms and are the only organisms categorized under Kingdom Monera. They occur nearly everywhere, from deep oceans to extreme hot springs.
Bacteria that are spherical in shape are specifically referred to as:
- A Vibrio
- B Bacillus
- C Coccus
- D Spirillum
Correct answer: Coccus
Based on shape, bacteria are grouped into four categories: spherical Coccus, rod-shaped Bacillus, comma-shaped Vibrio, and spiral Spirillum. The plural form of Coccus is Cocci.
Which of the following statements best describes the metabolic nature of bacteria as a group?
- A They are exclusively photosynthetic autotrophs.
- B They show the most extensive metabolic diversity.
- C They are all obligate intracellular parasites.
- D They lack any form of oxidative metabolism.
Correct answer: They show the most extensive metabolic diversity.
While bacterial structure is very simple, they are very complex in behavior. As a group, they show the most extensive metabolic diversity, ranging from autotrophy (photo/chemo) to vast heterotrophy.
Archaebacteria differ from other bacteria (Eubacteria) primarily in their:
- A Cell shape
- B Mode of reproduction
- C Cell wall structure
- D Presence of flagella
Correct answer: Cell wall structure
Archaebacteria have a different cell wall structure compared to Eubacteria. This specific feature is responsible for their survival in extreme conditions like high salinity and extreme heat.
Methanogens, which produce methane gas, are found in which habitat?
- A Deep-sea hydrothermal vents
- B Extremely salty water bodies and salt pans
- C Hot springs and acidic sulphur vents
- D Marshy areas and gut of ruminants
Correct answer: Marshy areas and gut of ruminants
Methanogens are a type of archaebacteria present in marshy areas. They also live in the gut of several ruminant animals like cows and buffaloes, helping in the production of biogas.
Cyanobacteria are also known as blue-green algae and are characterized by the presence of:
- A Chlorophyll a, like green plants
- B Chlorophyll b and c only
- C Fucoxanthin as main pigment
- D Phycobilins without chlorophyll
Correct answer: Chlorophyll a, like green plants
Cyanobacteria are photosynthetic autotrophs. They possess chlorophyll a, which is identical to that found in green plants, allowing them to perform oxygenic photosynthesis.
What is the function of specialized cells called 'heterocysts' found in Nostoc and Anabaena?
- A Carbon dioxide fixation
- B Atmospheric nitrogen fixation
- C Asexual spore formation
- D Water storage
Correct answer: Atmospheric nitrogen fixation
Some filamentous cyanobacteria like Nostoc and Anabaena have specialized, thick-walled cells called heterocysts. These cells create an anaerobic environment necessary for the enzyme nitrogenase to fix atmospheric nitrogen.
Which group of bacteria play a great role in recycling nutrients like nitrogen, phosphorous, iron, and sulphur?
- A Photosynthetic autotrophs
- B Chemosynthetic autotrophs
- C Parasitic heterotrophs
- D Saprophytic fungi
Correct answer: Chemosynthetic autotrophs
Chemosynthetic autotrophic bacteria oxidize various inorganic substances such as nitrates, nitrites, and ammonia. They use the released energy for ATP production and are vital for nutrient recycling.
The majority of bacteria in nature belong to which nutritional category?
- A Chemosynthetic autotrophs
- B Photosynthetic autotrophs
- C Heterotrophs
- D Holophytic
Correct answer: Heterotrophs
The vast majority of bacteria are heterotrophs, meaning they do not synthesize their own food but depend on other organisms or dead organic matter for food. Many are important decomposers.
Which of the following is NOT a human disease caused by bacteria?
- A Cholera
- B Typhoid
- C Tetanus
- D Influenza
Correct answer: Influenza
Cholera, typhoid, and tetanus are well-known bacterial diseases. Influenza is caused by a virus, not a bacterium.
Bacteria reproduce primarily by which method?
- A Budding
- B Fission
- C Fragmentation
- D Gametic fusion
Correct answer: Fission
The most common method of reproduction in bacteria is binary fission. Under unfavorable conditions, however, they can produce spores.
What occurs during the 'sort of sexual reproduction' observed in bacteria?
- A Fusion of two haploid gametes
- B Meiosis followed by syngamy
- C Transfer of DNA from one bacterium to another
- D Formation of a diploid zygote
Correct answer: Transfer of DNA from one bacterium to another
Bacteria do not perform true sexual reproduction involving gametes. Instead, they undergo a primitive form of DNA transfer from one cell to another, often via conjugation.
Which organisms are known as the smallest living cells and can survive without oxygen?
- A Cyanobacteria
- B Mycoplasma
- C Archaebacteria
- D Bacillus
Correct answer: Mycoplasma
Mycoplasma are organisms that completely lack a cell wall. They are the smallest known living cells and are unique because many of them are pathogenic and can survive in anaerobic conditions.
A characteristic feature of Mycoplasma is that they:
- A Possess a thick rigid peptidoglycan cell wall
- B Are resistant to many antibiotics that act on cell walls
- C Are exclusively autotrophic in their mode of nutrition
- D Are large multicellular branching filaments
Correct answer: Are resistant to many antibiotics that act on cell walls
Because Mycoplasma lack a cell wall, they are naturally resistant to antibiotics like penicillin that function by inhibiting cell wall synthesis. They are pleomorphic (can change shape) due to this lack of a rigid wall.
The colonies of cyanobacteria are generally surrounded by a:
- A Calcium carbonate shell
- B Gelatinous sheath
- C Siliceous frustule
- D Chitinous layer
Correct answer: Gelatinous sheath
Cyanobacteria often form blooms in polluted water bodies. Their colonies are typically encased in a mucilaginous or gelatinous sheath which helps in buoyancy and protection.
Halophiles are bacteria found in:
- A Hot volcanic springs
- B Extreme salty areas
- C Marshy wetland areas
- D Ice-cold polar water
Correct answer: Extreme salty areas
Halophiles are specialized archaebacteria that thrive in environments with very high salt concentrations. Their unique cellular membranes allow them to remain stable in such osmotic conditions.
Thermoacidophiles are typically found in environments with:
- A High salt and low temperature
- B High temperature and high acidity
- C Low temperature and high alkalinity
- D High oxygen and low temperature
Correct answer: High temperature and high acidity
Thermoacidophiles are archaebacteria that live in extreme conditions of high temperature (hot springs) and low pH (acidic conditions).
In the five-kingdom classification, Monera includes:
- A Only unicellular eukaryotes
- B Multicellular prokaryotes only
- C All prokaryotes
- D Only photosynthetic bacteria
Correct answer: All prokaryotes
The fundamental characteristic for inclusion in Kingdom Monera is having a prokaryotic cell structure (lacking a defined nucleus and membrane-bound organelles).
Which of the following bacterial shapes is comma-shaped?
- A Coccus
- B Vibrio
- C Bacillus
- D Spirillum
Correct answer: Vibrio
Vibrio is a bacterium that has a curved-rod, comma-like shape. A well-known example is Vibrio cholerae, the causative agent of cholera.
Citrus canker is a disease caused by:
- A Viruses
- B Fungi
- C Bacteria
- D Mycoplasma
Correct answer: Bacteria
Citrus canker is a significant plant disease caused by the bacterium Xanthomonas axonopodis. It affects the leaves, stems, and fruit of citrus trees.
Which of the following is a defining feature of organisms in Kingdom Monera?
- A Presence of a membrane-bound nucleus
- B Multicellular organization
- C Absence of membrane-bound organelles
- D Presence of chloroplasts
Correct answer: Absence of membrane-bound organelles
Organisms in Kingdom Monera are prokaryotic, meaning they lack a true nucleus and membrane-bound organelles like mitochondria or chloroplasts.
The genetic material in Monerans is typically found in which form?
- A Linear chromosomes inside nucleus
- B Circular DNA in nucleoid region
- C RNA strands in cytoplasm
- D Double nucleus system
Correct answer: Circular DNA in nucleoid region
Monerans have circular DNA located in a nucleoid region, as they lack a true nucleus.
Which structure is commonly found in bacterial cells but absent in eukaryotic cells?
- A Phospholipid cell membrane
- B Cytoplasmic ribosomes
- C Peptidoglycan cell wall
- D Cytoplasmic matrix
Correct answer: Peptidoglycan cell wall
Bacterial cell walls are made of peptidoglycan, which is not found in eukaryotic cells.
Which type of ribosomes are present in bacteria?
- A 80S ribosomes
- B 70S ribosomes
- C 60S ribosomes
- D 90S ribosomes
Correct answer: 70S ribosomes
Bacteria contain 70S ribosomes, which are smaller than the 80S ribosomes found in eukaryotic cells.
What type of cell organization is seen in Kingdom Monera?
- A Multicellular eukaryotic
- B Unicellular prokaryotic
- C Multicellular prokaryotic
- D Colonial eukaryotic
Correct answer: Unicellular prokaryotic
Kingdom Monera consists mainly of unicellular prokaryotic organisms.
Which of the following modes of nutrition is NOT seen in bacteria?
- A Chemoautotrophic nutrition
- B Heterotrophic mode of nutrition
- C Saprophytic decomposition
- D Parasitic multicellular feeding
Correct answer: Parasitic multicellular feeding
Bacteria do not exhibit multicellular feeding; they absorb nutrients directly, unlike multicellular organisms.
Which pigment is responsible for photosynthesis in cyanobacteria?
- A Chlorophyll-a
- B Chlorophyll-b
- C Carotene
- D Xanthophyll
Correct answer: Chlorophyll-a
Cyanobacteria contain chlorophyll-a, enabling them to perform photosynthesis similar to plants.
Which of the following is a feature of archaebacteria cell walls?
- A Presence of standard peptidoglycan layers
- B Complete absence of any cell wall structure
- C Presence of unique polysaccharides and proteins
- D Cell walls composed primarily of cellulose polymers
Correct answer: Presence of unique polysaccharides and proteins
Archaebacteria have cell walls without peptidoglycan and instead contain unique polysaccharides and proteins.
Which structure helps bacteria in locomotion?
- A Cilia
- B Pseudopodia
- C Plasmodesmata
- D Flagella
Correct answer: Flagella
Flagella are whip-like structures that enable bacterial movement.
Which of the following bacteria fix atmospheric nitrogen?
- A Escherichia coli
- B Staphylococcus
- C Vibrio
- D Rhizobium
Correct answer: Rhizobium
Rhizobium bacteria fix atmospheric nitrogen in root nodules of leguminous plants.
Which form of bacteria has a rigid spiral shape?
- A Coccus
- B Bacillus
- C Spirillum
- D Spirochete
Correct answer: Spirillum
Spirillum are spiral-shaped bacteria with rigid structure, unlike flexible spirochetes.
Which of the following is an example of chemosynthetic autotrophic bacteria?
- A Lactobacillus
- B Clostridium
- C Bacillus
- D Nitrosomonas
Correct answer: Nitrosomonas
Nitrosomonas obtains energy by oxidizing ammonia, making it a chemosynthetic autotroph.
Which term describes bacteria that require oxygen for survival?
- A Obligate aerobes
- B Anaerobes
- C Facultative anaerobes
- D Microaerophiles
Correct answer: Obligate aerobes
Obligate aerobes strictly require oxygen for respiration and survival.
Which of the following is a characteristic of Mycoplasma?
- A Presence of rigid cell wall
- B Defined nucleus
- C Multicellular structure
- D Lack of cell wall
Correct answer: Lack of cell wall
Mycoplasma lack a cell wall, making them resistant to antibiotics that target cell wall synthesis.
Which bacterial structure is involved in genetic recombination during conjugation?
- A Sex pili
- B Flagella
- C Capsule
- D Cell wall
Correct answer: Sex pili
Sex pili are specialized appendages that facilitate the transfer of genetic material between bacterial cells during conjugation.
Which of the following statements about bacteria is correct?
- A Bacteria are primarily harmful to humans
- B Bacteria rely on autotrophic nutrition for energy
- C Bacteria form multicellular structures
- D Bacteria exhibit diverse metabolic pathways
Correct answer: Bacteria exhibit diverse metabolic pathways
Bacteria have a wide range of metabolic diversity, including autotrophic and heterotrophic modes.
Which type of bacteria thrive in extremely salty environments?
- A Halophiles
- B Thermophiles
- C Methanogens
- D Barophiles
Correct answer: Halophiles
Halophiles are archaebacteria adapted to live in high salt concentrations.
What is the primary method of reproduction in bacteria?
- A Binary fission
- B Budding
- C Spore formation
- D Fragmentation
Correct answer: Binary fission
Bacteria primarily reproduce asexually through binary fission.
Which structure provides protection and helps bacteria survive harsh conditions?
- A Capsule
- B Pilus
- C Flagellum
- D Mesosome
Correct answer: Capsule
The capsule protects bacteria from desiccation and host immune responses.
Which group of Monerans are known for producing biogas?
- A Cyanobacteria
- B Methanogens
- C Halophiles
- D Actinomycetes
Correct answer: Methanogens
Methanogens produce methane gas in anaerobic conditions, contributing to biogas formation.