Last updated on December 14th, 2023 at 08:02 am
MCQ on Class 8 Science Microorganisms Friends and Foe
Test your knowledge on microorganisms as friends and foes with engaging MCQs from the chapter’Microorganisms: Friends and Foe
Which of the following statements is true about micro-organisms?
- a) They can be seen with the naked eye.
- b) They are harmful to all living organisms.
- c) They can only be observed with a microscope.
- d) They do not have any impact on the environment.
Answer: c) They can only be observed with a microscope.
Which group of micro-organisms includes amoeba and paramecium?
- a) Bacteria
- b) Viruses
- c) Protozoa
- d) Fungi
Answer: c) Protozoa
Which of the following micro-organisms is multicellular?
- a) Algae
- b) Protozoa
- c) Bacteria
- d) Virus
Answer: a) Algae
Bacteria are classified as:
- a) Multicellular micro-organisms
- b) Unicellular micro-organisms
- c) Viruses
- d) Fungi
Answer: b) Unicellular micro-organisms
Which bacteria are responsible for nitrogen fixation?
- a) Lactobacillus bacteria
- b) Rhizobium bacteria
- c) Spherical bacteria
- d) Rod-shaped bacteria
Answer: b) Rhizobium bacteria
Which of the following diseases is NOT caused by bacteria?
- a) Cholera
- b) Typhoid
- c) Tuberculosis (TB)
- d) Malaria
Answer: d) Malaria
What is the full form of AIDS?
- a) Acquired Immune Deficiency System
- b) Acquired Infectious Disease Syndrome
- c) Acute Immunodeficiency Syndrome
- d) Acquired Immune Deficiency Syndrome
Answer: d) Acquired Immune Deficiency Syndrome
Which disease is caused by Ent amoeba?
- a) Malaria
- b) Dysentery
- c) Tuberculosis (TB)
- d) Cholera
Answer: b) Dysentery
What is the common name for Plasmodium?
- a) Malarial Parasite
- b) Amoebic Parasite
- c) Protozoan Parasite
- d) Ent amoeba Parasite
Answer: a) Malarial Parasite
Algae are plant-like organisms that produce food through:
- a) Respiration
- b) Reproduction
- c) Photosynthesis
- d) Digestion
Answer: c) Photosynthesis
Which type of algae has the ability to fix nitrogen gas from the atmosphere?
- a) Chlamydomonas
- b) Spirogyra
- c) Blue-green algae
- d) Diatoms
Answer: c) Blue-green algae
Fungi obtain their nutrition by:
- a) Photosynthesis
- b) Respiration
- c) Feeding on dead matter
- d) Parasitism
Answer: c) Feeding on dead matter
What are some human diseases caused by fungi?
- a) Influenza and common cold
- b) Tuberculosis and pneumonia
- c) Ringworm and athlete’s foot
- d) Malaria and dengue fever
Answer: c) Ringworm and athlete’s foot
Which micro-organism is responsible for the formation of curd from milk?
- a) Virus
- b) Fungi
- c) Bacteria
- d) Protozoa
Answer: c) Bacteria
The bacterium involved in the formation of curd from milk is called:
- a) Lactobacillus
- b) Rhizobium
- c) Aspergillus
- d) Penicillium
Answer: a) Lactobacillus
What do Lactobacillus bacteria convert in milk during the curd formation process?
- a) Fat
- b) Protein
- c) Lactose
- d) Calcium
Answer: c) Lactose
The conversion of lactose into lactic acid by Lactobacillus bacteria leads to the formation of:
- a) Milk
- b) Cheese
- c) Yogurt
- d) Butter
Answer: c) Yogurt
What is an antibiotic?
- a) A disease-causing micro-organism
- b) A medicine that kills disease-causing micro-organisms
- c) A type of fungus
- d) A type of bacteria
Answer: b) A medicine that kills disease-causing micro-organisms
Which of the following is an antibiotic made from fungi?
- a) Penicillin
- b) Streptomycin
- c) Erythromycin
- d) Tetracycline
Answer: a) Penicillin
Where are Rhizobium bacteria found in association with plants?
- a) Leaf surfaces
- b) Stem tissues
- c) Flower petals
- d) Root nodules
Answer: d) Root nodules
Which plants commonly form a symbiotic relationship with Rhizobium bacteria?
- a) Grasses
- b) Trees
- c) Ferns
- d) Leguminous plants
Answer: d) Leguminous plants
What is the process of converting atmospheric nitrogen gas into nitrogen compounds called?
- a) Nitrogen fixation
- b) Nitrogen respiration
- c) Nitrogen synthesis
- d) Nitrogen absorption
Answer: a) Nitrogen fixation
What is the circulation of nitrogen between living things and the non-living environment called?
- a) Nitrogen fixation
- b) Nitrogen respiration
- c) Nitrogen cycle
- d) Nitrogen synthesis
Answer: c) Nitrogen cycle
The plant disease called ‘rust of wheat’ is caused by …….
- Virus
- Algae
- Fungi
- Bacteria
Answer: Fungi
Dengue is caused by a……………
- Virus
- None of These
- Protozoa
- Bacteria
Answer: Virus
Scientists who study microorganisms are known as ………
- Pedologist
- None of These
- Microbiologist.
- Ornithologist
Answer: Microbiologist
Malaria is caused by ………….
- Protozoa
- None of These
- Bacteria
- Virus
Answer: Protozoa
The insect which transmits disease-causing micro-organisms to humans is called a ……….
- Transmitter
- Carrier
- Messenger
- None
Answer: Carrier
The antibiotic ‘penicillin’ was discovered ‘Penicillium’ which is a ………….
- Fungus
- None of These
- Bacteria
- Algae
Answer: Fungus
The plant disease called ‘citrus canker’ is caused by …….
- Virus
- Bacteria
- Fungi
- Algae
Answer: Bacteria
Bacteria and fungi are used to make medicines called……….
- Vitamins
- Antibiotics
- Vaccines
- None
Answer: Antibiotics
Spiral-shaped bacteria are called ………
- Spirilla
- Bacilli
- Cocci
- None of These
Answer: Spirilla
The study of microorganisms is known as ………
- Pedology
- None of These
- Microbiology.
- Ornithology
Answer: Microbiology
The plant disease called ‘yellow vein mosaic of OKRA (bhindi)’ is caused by a ………
- Virus
- None of These
- Bacteria
- Protozoa
Answer: Virus
Rod-shaped bacteria are called ……….
- Cocci
- None of These
- Spirilla
- Bacilli
Answer: Bacilli
Who discovered the bacteria Bacillus anthracis which causes anthrax disease in animals in 1876?
- Robert Koch
- Louis Pasteur
- Oswald Avery
- None of These
Answer: Robert Koch
Microorganisms have a hard outer covering called ………
- Cyst
- None
- Bark
- Chitin
Answer: Cyst
Spherical-shaped bacteria are called …….
- Cocci
- Spirilla
- None of These
- Bacilli
Answer: Cocci
Edward Jenner discovered the vaccine for …………. in 1798.
- Polio
- Rabies
- Smallpox
- Varicella
Answer: Smallpox
