1. Tick the correct option:
1. The yeast multiply by a process called
(a) Binary fission (b) Budding
(c) Spore formation (d) None of the above
2. The example of protozoan is
(a) Penicillium (b) Blue green algae
(c) Amoeba (d) Bacillus
3. The most common carrier of communicable diseases is
(a) Ant (b) Housefly
(c) Dragonfly (d) Spider
4. The following is an antibiotics
(a) Alcohol (b) Yeast
(c) Sodium bicarbonate (d) Streptomycin
5. Yeast produces alcohol and carbon dioxide by a process called
(a) Evaporation (b) Respiration
(c) Fermentation (d) Digestion
6. The algae commonly used as fertilizers are called
(a) Staphylococcus (b) Diatoms
(c) Blue green algae (d) None of the above
7. Cholera is caused by
(a) Bacteria (b) Virus
(c) Protozoa (d) Fungi
8. Plant disease citrus canker is caused by
(a) Virus (b) Fungi
(c) Bacteria (d) None of these
9. The bread dough rises because of
(a) Kneading (b) Heat
(c) Grinding (d) Growth of yeast cells
10. Carrier of dengue virus is
(a) House fly (b) Dragon fly
(c) Female Aedes Mosquito (d) Butterfly
11. Yeast is used in the production of
(a) Sugar (b) Alcohol
(c) Hydrochloric acid (d) Oxygen
12. The vaccine for smallpox was discovered by
(a) Robert Koch (b) Alexander Fleming
(c) Sir Ronald Ross (d) Edward Jenner
13. Chickenpox is caused by
(a) Virus (b) Fungi
(c) Protozoa (d) Bacteria
14. The bacterium which promote the formation of curd
(a) Rhizobium (b) Spirogyra
(c) Bread mould (d) Lactobacillus
15.Plasmodium is a human parasite which causes
(a) dysentery (b) Sleeping sickness
(c) Malaria (d) All of the above
16. The bacterium Bacillus Anthracis was discovered by
(a) Edward Jenner (b) Alexander Fleming
(c) Louis Pasteur (d) Robert Koch
17. Carrier of malaria causing protozoan is
(a) Butterfly (b) Housefly
(c) Female Anopheles Mosquito (d) Cockroach
18. The process of conversion of sugar into alcohol is called
(a) Infection (b) Moulding
(c) Nitrogen fixation (d) Fermentation
19. Foot and mouth disease of cattle is caused by
(a) Fungi (b) Virus
(c) Algae (d) None of these
20. Which of the following is not a fungi
(a) Paramecium (b) Bread mould
(c) Penicillium (d) Aspergillus
1)b 2) c 3) b 4) d 5) c 6) c 7) a 8) c 9) d 10) c
11) b 12) d 13) a 14) d 15) c 16) d 17) c 18) d 19) b 20) a
2. Write the contributions of the following:
A. Louis Pasteur B. Edward Jenner C. Alexander Fleming D. Robert Koch
A. Microbes B. Pathogens C. Nitrogen Fixation
D. Pasteurization E. Preservatives F. Carriers G. Fermentation
4. Give two uses of microorganisms in the following areas:
i) Food Industry ii) Medicinal Use iii) Environment related
5. Give an activity to show the process of fermentation?
6. List few differences between Antibiotics and Antibodies?
7. Explain Nitrogen Cycle in detail with the help of a cyclic representation?
8. List some harmful effects of microorganism?
9. How can we control the spread of diseases caused by mosquitoes?
10. Why milk in polypacks does not get spoiled?
11.Why does sugar solution with yeast powder become alcoholic in taste?
12. Megha, a class VIII student was asked to submit a project report on mosquito transmitted diseases. She visited a nearby hospital where her aunt was staffed as a nurse. Her aunt took her to a patient suffering from malaria. Megha talked to the patient and asked him about his health and also took some flowers for him.
(a) Name the mosquito that spreads malaria.
(b) What is the name given to such organisms that transmit the diseases from infected to healthy persons?
(c) How can we control the spread of diseases by mosquitoes?
(d) Identify two important values as shown by Megha.
13. Kushal's family is happy as he became a proud father to a baby girl. Upon a routine visit to the hospital, the doctor advised him not to skip the vaccination schedule. While discussing the same at home, one of the family members suggested that vaccination is not necessary for a girl child. Kushal opposed this suggestion.
(a) What is vaccination?
(b) Name the scientist who prepared the first vaccine?
(c) Critically comment upon Kushal's viewpoint.
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To Plot the magnetic field with the help of fine iron filings (a) single bar magnet (b) two bar magnets, such that their opposite poles face each other (c) two bar magnets, such that their similar poles face each other.
1. Fine iron filings filled in a sprinkler (same kind of sprinkler used for salt or pepper).
2. A foolscap white sheet of paper.
3. Two bar magnets.
4. Two thick and wide books of same thickness.
1. Arrange the thick books in such a way that you get a flat smooth surface, wide enough for the fulls cape white sheet of paper.
2. Make a small gap between the books and insert a bar magnet between the gap.
3. Spread the white sheet of paper on the books and secure it with cello tape.
4. Sprinkle iron filings all over the paper evenly.
5. Tap the paper gently. You will observe that iron filings act like thousands of tiny magnetic compasses and align themselves along the magnetic lines of force as shown in figure Fig. 01. These lines come out of the magnet from the north pole and end up at south pole.
6. Now place two bar magnets in the gap between the books, such that north pole of one magnet is facing towards the south pole of other magnet as shown in figure : 02. Repeat the activity again and observe the magnetic field.
7. Now place two bar magnets in the gap between the books, such that north poles of both magnets face each other as shown in figure :03). Repeat the activity again and observe the magnetic field.
In this case you will find that at point P, between the two norths poles there are no iron filings. It is because there is no magnetic field at P. This is called neutral point.
Procedure (to be performed in the school laboratory)
The EJSMagnetic Field from Loops model computes the B-field created by an electric current through a straight wire, a closed loop, and a solenoid. The user can adjust the vertical position of the slice through the 3D field.
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