Test: Microorganisms : Friend Or Foe (Easy)

15 Questions MCQ Test Science Class 8 | Test: Microorganisms : Friend Or Foe (Easy)

This mock test of Test: Microorganisms : Friend Or Foe (Easy) for Class 8 helps you for every Class 8 entrance exam. This contains 15 Multiple Choice Questions for Class 8 Test: Microorganisms : Friend Or Foe (Easy) (mcq) to study with solutions a complete question bank. The solved questions answers in this Test: Microorganisms : Friend Or Foe (Easy) quiz give you a good mix of easy questions and tough questions. Class 8 students definitely take this Test: Microorganisms : Friend Or Foe (Easy) exercise for a better result in the exam. You can find other Test: Microorganisms : Friend Or Foe (Easy) extra questions, long questions & short questions for Class 8 on EduRev as well by searching above.

Common tick fever is caused by___________.

Solution: Tick fever is a parasitic infection caused by the species Babesia.


Microbes which have adapted themselves so that they can survive and even thrive in conditions that are normally fatal most lifeforms

Solution: Extremophiles are microorganisms that have adapted so that they can survive and even thrive in extreme environments that are normally fatal to most life-forms. Thermophiles and hyperthermophiles thrive in high temperatures.


Quinine, the remedy for malaria is extracted from

Solution: Quinine is the medication used to treat malaria. It is a white, bitter, crystalline alkaloid extracted from the bark of Cinchona.


A biodegradable insecticide has been obtained from.

Solution: Biodegradable insecticides are types of insecticides derived from natural materials as plants, bacteria, etc. Bioinsecticide from marigold flowers contains chemicals called thiophenes which are toxic to the larvae of mosquitoes that carry malaria and yellow fever. Bioinsecticide made from marigolds also contains repellent against major tomato pests: whiteflies, thrips, and spider mites.


Which of these are not included in the prevention of measles?

Solution: The vaccination is generally not given to infants because infants respond inadequately to the vaccine due to an immature immune system. Anti-measles antibodies are transferred from mothers who have been vaccinated against measles or have been previously infected with measles to their newborn children. However, such antibodies are transferred in low amounts and usually lasts six months or less. Infants under one year of age whose maternal anti-measles antibodies have disappeared become susceptible to infection with the measles virus. A second dose of the vaccine is usually given to children between the ages of four and five, to increase rates of immunity.


Which of the following statements is correct about vaccination?

Solution: Vaccination is the process of administration of the vaccine (antigenic material) into the body in order to stimulate the immune system and produce antibodies against specific antigens. It helps to attain resistance to a specific disease. A vaccine is an inactivated or heat-killed disease-causing microorganism. It involves the use of a weakened or harmless version of the pathogen. However, there are many diseases like malaria, dengue fever, AIDS which are not controlled by vaccination.


Babesia bigemina causes_____________.

Solution: Tick fever is a parasitic infection caused by Babesia bigemina.


Azolla is used as a biofertilizer as it has

Solution: Azolla is a pteridophyte and used as a biofertilizer because it has an association with nitrogen-fixing cyanobacteria Anabaena azollae.


Typhoid was discovered by

Solution: Karl Joseph Eberth was the first to describe the bacillus that was suspected to cause typhoid in 1880. Four years later, Georg Gaffky was a pathologist that confirmed this link, naming the bacillus Eberthella typhi, which is known today as Salmonella enterica.


A eukaryotic group that causes serious plant diseases comes under:

Solution: A fungus is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. Most plant diseases – around 85 percent – are caused by fungal or fungi-like organisms Monera is a kingdom that contains unicellular organisms with a prokaryotic cell organization (having no nuclear membrane), such as bacteria. A protist is any eukaryotic organism that is not an animal, plant, or fungus. The protists are unicellular eukaryotes of which few of them are parasitic, but do not cause diseases in plants Viruses are considered neither prokaryotes nor eukaryotes because they lack the characteristics of living things, except the ability to replicate (which they accomplish only in living cells).


Which of the following statement is not true for stirred tank fermentation?

Solution: Force pressurized air (or pure oxygen) into the water with diffusers. Allow the water to free fall through the air. This process releases any over-saturated gases and increases the surface area of the water so that more dissolved oxygen in the area can be exposed to the water.


Confusion technique uses

Solution: The aim of the confusion technique is to lay artificial pheromone trails or even to saturate the crop environment with the odor of synthetic pheromone, in order to confuse the males and prevent them from locating females. It is expensive and therefore not usually practical


Which of the following statements are correct?

A.polio vaccine is administered orally.

B. Most of the vaccines is taken intravenously.

C. Common cold communicable and most easily infectious disease caused by viruses.

D. Vomiting, acute diarrhoea, and muscular cramps are the symptoms of cholera.


Vaccines are the suspension of killed or weakened microorganism which generates the immune response. 

The common cold is caused by Rhinovirus. It is a communicable disease.

Cholera is an infectious disease, that causes severe watery diarrhea, which can lead to dehydration and even death if untreated. It is caused by eating food or drinking water contaminated with a bacterium, called Vibrio cholerae. Vomiting, acute diarrhea, and muscular cramps are the symptoms of cholera.




Which of the following causes chills and fever in malaria?

Solution: The fever and chills of malaria are associated with the rupture of erythrocytic-stage schizonts. In severe falciparum malaria, parasitized red cells may obstruct capillaries and postcapillary venules, leading to local hypoxia and the release of toxic cellular products.


Name the Living organism which we cannot see by the naked eye.

Solution: The microorganisms are microscopic bodies that cannot be seen directly with the naked eye. These organisms are of the size of microns. The study which deals with the microbes is known as microbiology. There are different types of microbes like bacteria, viruses, fungi, etc.