Class 9th Biology
Short
Questions
Chapter No: 2
Solving Biological Problems
Q1. What is
science? How does it work?
Ans: Science is the study of knowledge based on
observations and experiments. Scientific work is done by a specific method called the “scientific method”. It includes the following steps:
i.
Scientific
problem
ii.
Observation
and collection of data
iii.
Hypothesis
iv.
Experiments
v.
Conclusion
vi.
Law
or Principle
Q2. The Control group is important for scientific study. How?
Ans: Control group is a group that
remains constant throughout the experiment of a hypothesis. It is very
important for scientists, to find out the more accurate results of the experimental
group, which is comparable with the control group.
Q3.
What deductions are developed during the study of malaria?
Ans:
The following deductions were developed during
the study of malaria:
i.
If
plasmodium is the cause of malaria, then all the patients must have the
plasmodium in their blood.
ii.
If
mosquitoes are involved in the spreading of malaria, the plasmodium must be present
in the stomach of mosquitoes.
Q4.
How did Ronald Ross conduct the experiment to prove that mosquitoes are involved
in the spread of malaria?
Ans: Ronald Ross conducted an experiment on the female
Culex mosquito. He allowed this mosquito to bite the sparrow suffering from
malaria, and then allowed it to bite the healthy sparrow. As a result, the healthy
sparrow got malaria, and plasmodium was found in the sparrow’s blood. So, he proved
that these mosquitoes cause malaria in sparrows.
Q5.
At what step of the biological method hypothesis is accepted or rejected?
Ans:
At the step of “experiment” in the biological method the hypothesis is accepted or rejected.
