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?
