Which of the following reproduces only inside a host cell?
(a) Bacteria
(b) Virus
(c) Amoeba
(d) Fungus.
A disease in human beings caused by virus is _______.
(a) typhoid
(b) influenza
(c) dysentry
(d) cholera
Pathogenic micro-organisms present in host cells are killed by medicines called
(a) pain killer
(b) antibodies
(c) antibiotics
(d) vaccines
The two micro-organisms which live in symbiotic association in lichens are
(a) fungus and protozoa
(b) alga and bacteria
(c) bacteria and protozoa
(d) alga and fungus
The gas released during the preparation of bread is
(a) oxygen
(b) carbon dioxide
(c) nitrogen
(d) sulphur dioxide
The disease caused by a protozoan and spread by an insect is _________.
(a) dengue
(b) malaria
(c) polio
(d) measles
Paheli dug two pits, A and B, in her garden. In pit A, she put a polythene bag packed with some agricultural waste. In pit B, she dumped the same kind of waste but without packing it in a polythene bag. She, then covered both the pits with soil. What did she observe after a month?
(a) Waste in pit A degraded faster than that in pit B.
(b) Waste in pit B degraded faster than that in pit A.
(c) Waste in both pits degraded almost equally.
(d) Waste in both pits did not degrade at all.
Very Short Answer Type Questions
Unscramble the jumbled words underlined in the following statements.
(a) Cells of our body produce santiidobe to fight pathogens.
(b) curbossulite is an air-borne disease caused by a bacterium.
(c) Xanrhat is a dangerous bacterial disease.
(d) Yeasts are used in the wine industry because of their property of meronettinaf.
Suggest a suitable word for each of the following statements.
(a) Chemicals added to food to prevent growth of microorganisms.
(b) Nitrogen-fixing microorganism present in the root nodules of legumes.
(c) Agent which spreads pathogens from one place to another.
(d) Chemicals which kill or stop the growth of pathogens.
Match the names of scientists given in Column A with the discovery made by them given in Column B.
Name one commercial use of yeast.
Name the process in yeast that converts sugars into alcohol.
In the soil, which nutrient is enriched by blue-green algae (cyanobacteria)?
Why should we avoid standing close to a tuberculosis patient while he/she is coughing?
Polio drops are not given to children suffering from diarrhoea. Why?
Paheli watched her grandmother making mango pickle. After she bottled the pickle, her grand mother poured oil on top of the pickle before closing the lid. Paheli wanted to know why oil was poured? Can you help her understand why?
Short Answer Type Questions
Match the microorganisms given in the Column A to the group to which they belong in Column B.
Classify the following into friendly and harmful microorganisms. Yeast, malarial parasite, Lactobacillus, bread mould, Rhizobium, Bacillus anthracis
While returning from the school, Boojho ate chaat from a street hawker. When he reached home, he felt ill and complained of stomach ache and fell ill. What could be the reason?
What will happen to ‘pooris’ and ‘unused kneaded flour’ if they are left in the open for a day or two?
(a) Name two diseases that are caused by virus.
(b) Write one important characteristic of virus.
Long Answer Type Questions
Observe the Fig.2.1 and answer the questions that follows.
(a) Write the name of the disease.
(b) Name the causative agent of this disease?
(c) How does the disease spread from one plant to another?
(d) Name any two plant diseases and the microbes that cause them.
How do vaccines work?
Observe the set up given in Fig. 2.2 and answer the following questions.
(a) What happens to the sugar solution in A?
(b) Which gas is released in A?
(c) What changes will you observe in B when the released gas passes through it?
Observe the Fig.2.3 and answer the following question
(a) Name the microorganism and the group to which it belongs.
(b) Name the food item on which the organism grows.
(c) Does it grow well in dry or in moist conditions?
(d) Is it safe to eat infected bread?
Give reasons for the following.
(a) Fresh milk is boiled before consumption while processed milk stored in packets can be consumed without boiling.
(b) Raw vegetables and fruits are kept in refrigerators whereas jams and pickles can be kept outside.
(c) Farmers prefer to grow beans and peas in nitrogen deficient soils.
(d) Mosquitoes can be controlled by preventing stagnation of water though they do not live in water. Why?
How can we prevent the following diseases?
(a) Cholera
(b) Typhoid
(c) Hepatitis A
Answers
virus
influenza
antibiotic
algae and fungai
carbon dioxide
malaria
waste in pit B degrade faster
Answer:
Hope It Helps You and Please Mark As The Brainliest
Explanation:
1) Virus
2)Typhoid
3)Algae And Fungus
4)Carbon Dioxide
5)Malaria
6)Waste In Pit B Will Degrade Faster Than A
7)Cells of our body produce antibodies to fight pathogens
8)Tuberculosis is an infectious air-borne disease caused by a bacterium
9)Anthrax is a dangerous bacterial disease
10)Yeasts are used in the wine industry because of their property of Fermentation
11)Sodium Benzoate And Sodium Meta Bisulfite
12)Rhizobium
13)Carrier
14)Antibiotic
15)Fermentation
16)Making Wine
17)Somebody who has TB in his /her lungs can put the bacteria into the air, when he/she is coughing, talking or sneezing. If you are nearby you may breathe in these bacteria and become infected.
18)Diarrhea at OPV receipt was associated with vaccine failure to poliovirus types 1 and 3 only after OPV2. These data support the current recommendation that children with diarrhea receive OPV and be re immunized once their illness resolves.
19)Vaccines contain weakened or inactive parts of a particular organism (antigen) that triggers an immune response within the body. Newer vaccines contain the blueprint for producing antigens rather than the antigen itself
20)Raw vegetables and fruits are kept in refrigerators whereas pickles and jams are kept outside. It is because pickles and jams contains some preservatives such as sugar, salt and other ingredients in them. Though, pickles and jams do not easily get spoil by bacteria, air or other factors when you are kept them outside