9th Biology Chapter # 2 All Punjab Board Papers | 5 Years Old Board Papers Short questions | Repeated short questions in all Board Papers

  CHAPTER No. 2

1.                  What is science? Define biological method.  OR What is meant by Biological Method?       

Ans:   Science is the study in which observations are made, experiments are done and logical consequences are drawn in order to understand the principles of nature.

            BIOLOGICAL METHOD: The scientific method in which the biological problems are solved is termed as biological method.

2.                  How can we say that man has always been a Biologist?

Ans:    Man has always been a biologist. He had to be a biologist in order to live. Early in history, he was a hunter of animals and a gatherer of fruits, seed, roots etc.

3.                  Write the role of biological method in biology.

Ans:   It has played an important part in the scientific research for almost 500 years. From Galileo’s experiment in the 1590’s to current research the biological method has contributed to the advancements in medicine, ecology, technology etc. It has ensured the quality of data for public use.

4.                  What means by Biological problem.     

Ans:   A biological problem is a question related to living organisms that is either asked by someone or comes in biologists mind by him.

5.                  Write down the names of main steps of biological method.

Ans:   1- Recognition of the biological problem.                                2- Observations

            3- Formulation of hypothesis                      4- Deductions

            5- Experimentation                                        6- Summarization of results

            7- Reporting the results

6.                  Describe the recognition of the biological problem.

Ans:   Biologists go for adopting biological method when they encounter some biological problem. A biological problem is a question related to living organisms that is either asked by someone or comes in biologist’s mind by himself.

7.                  Define observation. How many types of it are there?

Ans:   Observations are made with five senses of vision, hearing, smell, taste and touch.  Observation may be both qualitative and quantitative.

            Quantitative observations are considered more accurate than qualitative ones because the quantitative observations are invariable and measureable and recorded in terms of numbers.

8.                 Define Quantitative and Qualitative Observations.

Ans:   Quantitative Observations:

            These are in invariable and measureable and can be recorded in terms of numbers.

            Qualitative Observations:

            These are variable and non-measureable and cannot be recorded in terms of numbers.

9.                  Why quantitative observations are better in biological method?

Ans:   Because quantitative observations are invariable and measurable and can be recorded in terms of numbers.

10.              Give two examples of quantitative observation.

Ans:   1- The freezing point of water is 0^oC. And that of boiling point of water is 100^oC.

            2- A liter of ethanol is 789g and that of water is 1000g.

11.             Give two examples of qualitative observations,

Ans:   The freezing point of water is lower than the boiling point. A liter of water is heavier than a liter of ethanol.

12.              Define hypothesis.                                                                      

Ans:   The tentative explanation of observations are called hypothesis.

13.              How a hypothesis formulate?

Ans:   A biologist organizes his/her and other observations into data form and constructs a statement that may prove to be answer of the biological problems under study, this tentative explanation of observations is called a hypothesis.

14.             What is the role of hypothesis?

Ans:   Observation do not become scientific observations until they are organized and related to a question. Biologist organizes his/her and others’ observations into data form and constructs a statement that may prove to be the answer of the biological problem under study.

15.             Write characteristics of a hypothesis./ Write two qualities of good hypothesis.                                               

Ans:  It should be general statement.

            It should be a tentative idea.

            It should agree with available observations.

16.             What is meant by deduction?                                                 

Ans:   Deductions are the logical consequences of hypothesis.

17.             Write down two words used for “Deduction”.

Ans:   Two words used for deduction are “if and then”.

18.             What is an experimental group?

Ans:   A group in which one variable is missing.

19.            What is control group?       

Ans:   Control group: A group in which no variable is missing.

20.             What is difference between control and experimental group?  OR  What is meant by "Control" in Experiments?

Ans:   In science when doing the experiment, it must be a controlled experiment. The scientist must contrast an “experimental group” with a “control group”. The two groups are treated exactly alike except for the one variable being tested. For example, in an experiment to test the necessity of carbon dioxide for photosynthesis, one can contrast the control group (a plant with freely available carbon dioxide) with an experimental group (a plant with no carbon dioxide available). The necessity of carbon dioxide will be proved when photosynthesis occurs in the control group and does not occur in the experimental group.

21.              How do we summarize results?                                 

Ans:   Biologist gathers actual, quantitative data from experiments. Data for each of the groups are then averaged and compared statistically to draw conclusions. Biologist also uses statistical analysis.

22.              How the reporting of results is done?                       

Ans:   Biologists publish their findings in scientific journals and books, in talks at national and international meetings and in seminars at colleges and universities. Publishing of results is an essential part of scientific method. It allows other people to verify the results or apply the knowledge to solve other problems.

23.              Describe the meaning of words "mala" and "aria".         

Ans:   Mala means bad.  Aria means air.  A disease of bad air.

24.              What is the use of quinine?

Ans:   Quinine was the only effective remedy for malaria.

25.         What were the major observations of Malaria in the last part of 19thcentury?

Ans:   1- Malaria and marshy areas have some relation.

            2- Quinine is an effective drug for treating malaria.

            3- Drinking the water of marshes does not cause malaria.

            4- Plasmodium is seen in the blood of malarial patient.

            5-People who slept outdoors were more likely to get malaria than those who slept indoors.

            6- Individuals who slept near smoky fire usually did not get malaria.

26.              Write contribution of French Army Doctor Laveran.

Ans:   He began to search for the cause of malaria. He took a small amount of blood, from a malarial patient and examined it under microscope. He noticed some tiny living creatures. The organism was given a name plasmodium.

27.              Describe two important observations of A.F.A King about malaria.

Ans:   The observations of A.F.A king are

            (i) Individuals who slept near a smoky fire did not get malaria.

            (ii)People who slept out doors were more likely to get malaria then those who slept indoors.

28.              Why Ronald Ross used sparrow in his experiment?

Ans:   Ronald Ross used sparrow in his experiments because using human being for experiments was so serious for life, because malaria was a serious problem at that time.

29.              What is an incubation period?                                    

Ans:   The period between the entry of parasite in host and the appearance of symptoms is called in incubation period.

30.             Write the role of A.F.A King. / Write two observation of A.F.A King.

Ans:   A.F.A king listed 20 observations about malarial problems. He suggested hypothesis i.e.

            “Mosquitoes transmit plasmodium and so are involved in the spread of malaria. He also made deductions i.e.

            “Plasmodium should be present in mosquitoes” A mosquito can get plasmodium by biting malarial patient.

31.              Why Culex and Anopheles Mosquitoes are well known?

Ans:   Anopheles mosquito causes malaria in man while culex mosquito causes malaria in sparrows.

32.              Why do the welts appear after mosquito bites or leaves the skin?

Ans:   The reason is that when mosquito bites, the red plumpness appear is not a reaction to the wound but an allergic reaction to the saliva. In most cases itching, sensation and swellings subsides within the several hours.

33.              How a theory is formulated?

Ans:   when a hypothesis is given a repeated exposure to experimentation and is not falsified, it increases biologists’ confidence in hypothesis. Such well-supported hypothesis may be used as the basis for formulating further hypothesis which are again proved by experimental results.

34.              What is meant by productive theory? / Write two benefits of productive theory.                                                             

Ans: Productive theory keeps on suggesting new hypothesis and so testing goes on.

35.              What is difference between theory and law?/ What are theories.  OR  How does a theory become a law of principle?                             (3 Time) (2017)

Ans:  

Theory	Law
The hypothesis that stand the test of time (often tested never rejected), are called theories.	If a theory survives doubtful approach and continues to be supported by experimental evidence, it becomes a law or principle.

36.              What is scientific Law? Give two examples.

Ans:   A scientific law is a uniform fact of nature. It is an irrefutable theory. Hardy Weinberg law, Mendel’s laws of inheritance are the examples of scientific laws.

37.              Write two examples of Biological Laws.                       

Ans:   Hardy Weinberg law, Mendel’s laws of inheritance.

38.              How data is organized?

Ans:   In order to formulate and then to test the hypothesis, scientist collect and organize data. Prior to conducting an experiment, it is very important for a scientist to describe data collection methods. It ensures the quality of experiment. Data is organized in different formats like graphics, tables, flow charts, maps and diagrams.

39.              What is meant by Ratio and Proportion?    

Ans:   Ratio:  When a relation between two numbers e.g. “a” and “b” is expressed in terms of quotient (a/b), it is called ratio of one number to the other.

            Proportion: Proportion means to join two equal ratios by the sign of equality.

40.              Define Bioinformatics.                                                          

Ans:   Bioinformatics refers to the computational and statistical techniques for the analysis of biological data