AP State Syllabus AP Board 8th Class Biology Important Questions Chapter 3 Story of Microorganisms 2
AP State Syllabus 8th Class Biology Important Questions 3rd Lesson Story of Microorganisms 2
8th Class Biology 3rd Lesson Story of Microorganisms 2 1 Mark Important Questions and Answers
What are antibodies?
Whenever a disease causing microorganisms enter in our body, it produces some de¬fenders to fight against them, these are called antibodies.
Which one is better to take antibiotics or vaccines?
Vaccines are better than antibiotics when the disease is prevented by vaccine.
Ex: Tuberculosis, Tetanus, etc.
What questions do you ask on role of mosquitoes and houseflies in spreading the diseases like Malaria and Swine flu?
- How can we be safe, without affected by malaria and typhoid?
- Which organisms spread diseases like malaria and typhoid?
What is ‘Triple Antigen Vaccine’?
D.P.T vaccine which prevents
- Pertusis (Wooping cough)
What is Tet – vac?
Tet – vac is the vaccine that is used to prevent Tetanus.
What is M.M.R vaccine?
M.M.R is the vaccine that prevents the
Name the vaccine that prevents T.B.
B.C.G (Bacillus Cardio Gram)
What is the mode of transmission of Dengue disease?
Aedes Mosquitoes spread Dengue disease.
8th Class Biology 3rd Lesson Story of Microorganisms 2 2 Marks Important Questions and Answers
Mention different questions to know about antibiotics.
- What are antibiotics?
- In which year penicillin was announced as antibiotic?
- Can antibiotics destroy the viruses?
- Write different types of antibiotics.
Prepare different questions to know the importance of vaccines.
- Name the scientist who invented vaccines first.
- What type of materials used for preparation of vaccines?
- Name the vaccine which is used to prevent rabies.
- Name the disease which is eradicated by vaccine.
Ask different questions about the significance of microbes.
- Name different nitrogen fixing microbes.
- Can all microbes useful to mankind?
- What will happen if vaccines are not invented?
- Write about significance of microbes.
Make a sketch of Nostoc.
How is preservation of food helps us?
- Preservation prevents spoilage of food.
- It helps us to store food for a longer time without spoilage.
- Variety of food items may be available in off seasons also.
8th Class Biology 3rd Lesson Story of Microorganisms 2 4 Marks Important Questions and Answers
Which one is better to take antibiotics or vaccines? Why?
Antibiotics are small molecules or compounds that are effective in treating infections caused by organisms such as bacteria, fungi and protozoa. Some antibiotics act by killing the bacteria while others prevent the bacteria from multiplying, leaving your own immune system to ‘mop them up’.
Vaccines are dead or inactivated organisms or compounds that are used to provide immunity to a particular infection or disease.
Vaccines are used to prevent infection, particularly viral infections. Vaccines are produced from portions of viruses or viruses that are rendered harmless.
The killed or modified virus is introduced into the body where it stimulates part of the body’s natural defenses against infection without causing the illness itself.
Because of this, if the body is exposed to the specific virus in the future, it will recognize it and can fight the infection off much more quickly and effectively, meaning that you don’t succumb to the illness.
Hence vaccines are better than antibiotics when the disease is prevented by vaccine. Ex: Tuberculosis, Tetanus, etc.
Refrigerator helps us in saving health and money. Can you explain?
Food and drink, being organic in origin, does not last forever. Shortly after food is bought or prepared it will begin to spoil, quickly becoming inedible through the effects of bacteria. By lowering the temperature of the food through refrigeration, you can slow or even temporarily halt the effects of bacteria, making the food stay edible longer.we can also transport fruits vegetables and other food items up to long distances by using refrigerators. Refrigerator is more useful to keep vaccines and medicines for long time. Hence we can save money and as well as health.
Take root nodules of any pulse or leguminous plants crush on a slide, and draw a rough sketches of what you observe under microscope.
Can you give some important key points you noticed that scientists followed in their inventions and discoveries?
Invention of microscope is most important one to find out microorganisms. Basing on this several inventions were made, which break the unsolved problems since 400 years. This credit goes to Antonie van Leeuwenhoek who invented single lens powerful microscope, which could magnify the object 300 times. His curiosity and skill of making powerful lenses were the secrets of this invention of powerful microscope.
Dr. Alexander Flemming observed some fungi were preventing the growth of bacteria in his experiments. He separated the substances released by the fungus and tested it on some other disease causing bacteria. This substance also killed many other diseases causing bacteria and named it as Pencillin. The discovery of pencillin paved the way to the discovery of many antibiotics like streptomycin, erythromycin etc.
After several attempts Ross suddenly realized that he used the wrong species of mosquitoes in his experiments. His assistant brought larvae, which hatched to several dappled winged mosquitoes. Delighted with this capture Ross identified Anopheles mosquito is the host for malarial parasite.
Which invention is most important one related to microorganisms? Can you explain the reasons why it is so important?
Invention of microscope is most important one to find out microorganisms. Basing on this several inventions were made, which break the unsolved problems since 400 years. This credit goes to Antonie van Leeuwenhoek who invented single lens powerful microscope, which could magnify the object 300 times. His curiosity and skill of making powerful lenses were the secrets of this invention of powerful microscope. Later several microbes were identified by using microscopes. This provides a good source to recognize several diseases and treatment by vaccines and antibiotics.
What are antibodies? When do they develop? How they help us?
Whenever a disease causing microorganisms enter in our body, it produces some defenders to fight against them, these are called antibodies. The lymphocytes of white blood cells develop antibodies against to the antigen of pathogen. Antibodies fight the disease causing microorganisms and make resistant to particular strains. Antibodies are used by the immune system to identify and neutralize foreign objects such as viruses and bacteria.
If there are no microorganisms on the earth what will happen?
Microorganisms are present everywhere, they are to be found in air, water, soil within the bodies of animals and plants. Some microorganisms are very useful and help us in many ways while some of them are harmful. Microorganisms are most essential to maintain inorganic and organic cycles, to give freshness to the nature by degrading waste organic matter and as well as to fight against harmful microorganisms. Hence no life will be sustained in the nature if there are no microorganisms on the earth.
Prepare a table showing some of plant diseases, causative microorganisms and mode of transmission.
|Name of the plant disease
|Mode of transmission
|1. Citrus canker
|Bacteria, Xanthomonoss citri
|2. Red rot of sugarcane
|3. Tikka disease of groundnut
|4. Tobacco mosaic
|5. Smut disease of rice
If there are no microorganisms on the earth what will happen?
- If micro organisms are not present on earth the earth will be full of dead organisms and plants.
- The plants can not fix the atmospheric nitrogen in the soil.
- We can not get fermented products.
- The life becomes impossible on the earth.
8th Class Biology 3rd Lesson Story of Microorganisms 2 Important Questions and Answers
Many people to. a colony are suffering from ‘Cholera’. What do you think could be the reason?
- The main reasons for the spread of cholera is consumption of contaminated food and water. House flies rapidly spread this disease among people.
- I would imagine that people were not following personal hygienic practices before consuming food and water.
- Perhaps people might not be keeping their surroundings clean and hygienic.
- Perhaps the people might have poor sanitary conditions.
Suggest any two methods of fish preservation.
What is symbiosis? Give two examples for it.
- In Greek language, symbiosis means “living together”.
- Symbiosis is any type of a close and long term biological interaction between two different biological organisms in which both are benefited.
- Examples for symbiotic relationship is Rhizobium. Rhizobium bacteria is living in the root nodules of legume plants.
- Rhizobium fixes the atmospheric nitrogen in the form of nitrates which are very essential for the growth of plants. Inturn legume plants provide shelter for Rhizobium. Here, both are benefited.
- Another example for symbiosis is Lichens. Here, we can see the symbiotic relationship between Algae and Fungi.
In an experiment if we keep the dosa dough in Bacillus free chamber, what changes can you observe in the dosa dough after one day?
- Fermentation of dosa dough will not take place.
- The volume of the dosa dough will not increase and it will not turn into spongy texture.
Classify the given below microorganisms into useful and harmful microorganisms.
Plasmodium, Lactobacillus, Rhizobium, Pencillium, Yeast, Virus.
- Lacto bacillus
What will happen if we add butter milk to chilled milk?
If we add a few drops of butter milk to chilled milk 1) the milk will not turn into curd. It is because, cold milk won’t provide the conditions to grow lactobacillus. Hence, curd will not be formed.
If you are going to conduct a quiz on micro-organisms, what type of questions do you prepare for the quiz programme?
- Can you name the scientist who discovered the pencillin?
- Name the bacteria that converts the milk into curd.
- Can you name the food items that can be preserved through pasteurisation?
- Can you name the microorganism which is very helpful in the preparation of alcohol?
What is the name of the nitrogen fixation bacteria in the root nodules?
What precautions do you take to avoid diseases?
- We should consume boiled, purified water and healthy food daily.
- Keep our surroundings neat and clean.
- We should take vaccines to prevent different diseases.
- We should practice personal hygiene and good sanitary habits.
Defecation in open areas spreads micro-organisms easily. Write some slogans to conduct a rally to protect us from micro-organisms.
- Keep your country clean by keeping your area clean.
- Stop being so open….. else everything is broken.
- Use a toilet. Don’t let anything spoil it,
- Use a toilet – to achieve Swach Bharath.
Draw a table of microorganisms and its diseases.
Microorganisms : Virus, Bacteria, Protozoa, Arthropods.
Disease: Scabies, Malaria, Polio, Typhoid.
Why is the idly or dosa batter prepared one day before?
If we prepare idly or dosa batter one day before, fermentation occurs in it, carbondioxide gas fill the batter increasing it’s volume and makes it spongy.
Read the following passage and answer the following questions.
When an infected person sneezes or coughs, the pathogens enter the air. When this air containing pathogens enters into the body of a healthy person, it may cause cold. These type of diseases which spread from infected people to healthy ones are known as “communicable diseases”. These get spread through air, water, food or through physical contact of infected person or through insects like houseflies and mosquitoes. Common cold, conjunctivitis, typhoid, smallpox, chickenpox, swine flu, tuberculosis are some examples of communicable diseases. Some insects and animals carry diseases causing microorganisms. They are called as ‘vectors’. The microorganism ‘plasmodium’causes malaria. The female Anopheles mosquito carries plasmodium and thus is a vector. Mosquitoes are vectors for other diseases as well. By controlling mosquitoes, we can prevent dis¬eases caused by them. Mosquitoes breed in stagnant water. We should be careful not to let water collect anywhere in our surroundings, including left over waste pots, waste flower pots, tyres, bowls etc.
a) What are communicable diseases? Give examples.
b) What are vectors?
c) Name the vector which spreads malaria.
d) How do you prevent spread of malaria?
a) The diseases which spread from infected people to healthy ones are known as “communicable diseases”.
Eg: Conjuctivitis, Common cold, Smallpox, Rubella, Typhoid, etc…
b) The insects and animals which carry disease causing microorganisms are called as “vectors”.
c) Female Anopheles mosquito.
d) By controlling mosquito population.