Question

QUESTION BANK
Class:- VIII
Q1. Can microorganism can seen with naked eye? If not, how can they be
02. How yeast help in baking?
Q3. Why viruses are said to be unique?
04. Siate the role of microorganism in-
a Cleaning the environment
b. Fuel production
C Sewage treatment
d. Food industry
e Agriculture
05. What do you understand by food preservation? Describe its three m
06. What are communicable diseases? List the ways by which commun
07. Why does food stay fresh for a longer time when stored in a refrige
08. What is food poisoning? Write any three symptoms of food poison
09. Name the microorganism help in production of alcohol​

Answer 1

Answer:

q1. No,we can see only microscopes.

q2. when yeast is mixed in dough for making bread, the yeast reproduces rapidly and gives out carbon dioxide gas during respiration The bubbles of carbon dioxide gas fill the dough and increase its volume.

q3. this is because diseases caused by viruses cannot be treated with antibiotics.

q4. (a)microorganisms decompose the harmful and smelly dead remains of plants and animals, animals wastes.

q5. The process in which the food materials are given a suitable physical or chemical treatment to prevent their spoilage is called food preservation.

• preservation of food by sun drying.
• preservation of food by common salt
• preservation of food by heating.

q6. those microbial diseases which can spread from infected persons to a healthy person through air, water, food or physical contact, etc. are called communicable diseases.

q7.Low temperature inhibits the growth of microorganisms, then the food does not get spoiled easily.

q8. the diseases caused due to the presence of large amounts of microorganisms in the food or due to the presence of toxic substances in food formed by the action of microorganisms is called food poisoning.

vomiting, fever and Diarrhoea

q9. yeast

hope it helps you

Answer 2

Explanation:

ans 1 no they can't be seen through our naked eye. they can be seen by a microscope.

ans 2 yeast has some properties that make the cake bread double.yeast reproduces rapidly and produces carbon dioxide during respiration which fills the dough and increases the volume.

ans 3 viruses are unique because no antibiotics can be used to treat them.

ans 4 a. they convert the dead plants and animals into humus and also fix up the nitrogen which helps in cleaning of environment.

b. they are used for making alcohol. yeast is used for it.

c. microorganisms purify it.

d. they are used in pickels cheese and many other items.

e. they fix up nitrogen which provides health and growth to plants.

ans 5 chemicals that are used to prevent the attack of disease causing microbes are called preservatives. eg salt oil etc.

ans 6 communicable disease spread from infected person to a healthy person through food air water and contact. eg cough etc

ans 7 because the level of moisture is low due to cold which prevent the attack of microbes.

ans 8 consumption of food spoilt by microbes causes food poisoning.

symptoms are vomiting not getting hungry for a longer time and fever also.

ans 9 yeast is used all over the world for production of alcohol.

hope it helps. plz mark me as brainliest.