Sample viva questions

DAV Public School, Kailash Hills

XII Practicals( 2015-16)

Sample Viva questions

1.       How many pairs of salivary glands are found in human beings?

2.       What are enzymes? Give two most important characteristics of enzymes.

3.       Why are enzymes referred to as biocatalyst?

4.       Why is NaCl added in the starch solution while testing salivary amylase activity?

5.       What are the end products of salivary amylase activity?

6.       What is achromic point?

7.       Did all three sets of tubes reach achromic point (while studying effect of pH and temperature)? If not , why so?

8.       What do you mean by optimum temperature, pH, and denaturation of enzyme?

9.       Why do we add NaCl while extracting DNA?

10.   Why is liquid soap added to the solution for extracting DNA out of cells?

11.   Why is chilled ethanol added while separating DNA fibres from the solution?

12.   Name the various types of soil.

13.   On what basis are various types of soils classified?

14.   Which component of soil is responsible for retention of water?

15.   Why is soil water important?

16.   Name the soil which can retain maximum and minimum amount of water.

17.   Which type of soil is ideal for plant growth?

18.   How is the study of soil structure important for selecting crops to be grown?

19.   How is pH of soil important and how is humus important for soil?

20.   Why is mitosis termed as equational division and meiosis as reductional division?

21.   What do you mean by term karyokinesis and cytokinesis?

22.   At what stage of cell division does nuclear membrane reappear?

23.   In which stage of cell division chromosomes are seen best?

24.   What are the main events occurring during different phases of mitosis and meiosis?

25.   What are the advantages of working with pea plant in dihybrid and monohybrid cross?

26.   What is the Law of Dominance, Law of segregation and Law of Independent Assortment?

27.   What are pedigree charts and how are they useful in genetical studies?

28.   What is colour blindness? Mention its genetical basis.

29.   What is haemophilia? Mention its genetical basis

30.   What is parasite? What do you understand by primary and secondary host?

31.   What causes Amoebic dysentery, malaria, Ascariasis?  Mention the symptoms and mode of infection?

32.   Name the ecological problems faced in dry xerophytic conditions.

33.   Name a few adaptations found in xerophytic plants to prevent loss of water.

34.   Name a few adaptations to manage minimum loss of water in desert animals..

35.   Name ecological problems in aquatic mode of life.

36.   Name ecological adaptations in aquatic mode of life.

37.   What is full form of BOD? What is DO and COD?

38.   What is significance of BOD in an aquatic ecosystem?

39.   What is the relationship between DO and BOD?