MCS-SCIENCE-CLASS 8C

HOMEWORK                  MICROORGANISMS -FRIEND AND  FOE          16th APRIL, 2020

Q9.How do vaccines work?

Q10.Match the following:

  COLUMN I                                                  COLUMN II
a)Louis Pasteur                                           i) Penicillin
b)Robert Koch                                            ii)Anthrax Bacterium
c)Edward Jenner                                        iii)Fermentation
d)Alexander Fleming                                 iv)Small pox vaccine

Q11.Why should we avoid standing close to a  tuberculosis patient while he is coughing?

Q12.What will happen to pooris and unused kneaded dough if left in open for a day or two?

Q13.Give reasons for the following:
a) Farmers prefer to grow beans and peas in nitrogen deficient soil.

b)Raw vegetables and fruits are kept in refrigerator whereas jams and pickles can be left outside.

c)Fresh milk is boiled before consumption while processed milk is stored in packets and can be consumed without boiling.