Which of the following disease in the late 1800s puzzled bacteriologists at that time?
a) malaria
b) pneumonia
c) tobacco disease
d) tuberculosis
Explanation: this disease was not due to bacteria
Who first demonstrated that tobacco was infected by virus?
a) Louis Pasteur
b) Robert Koch
c) W. M. Stanley
d) Iwanowsky
The true nature of viruses first became evident when ……..prepared an extract of tobacco mosaic virus.
a) Louis Pasteur
b) Robert Koch
c) W. M. Stanley
d) Iwanowsky
Which of the following virus was first identified?
a) HIV
b) SARS
c) TMV
d) COVID-19
Explanation: TMV= tobacco mosaic virus first identified in 1935 by W. Stanley
Classification of Viruses:
The genome of the most animals and higher plants is……
a) DNA
b) RNA
c) protein
d) both a and b
