Board Paper of Class 12-Science 2016 Biology Abroad(SET 2) - Solutions
(i) There are a total of 26 questions and five sections in the question paper, All questions are compulsory.
(ii) Section A contains question number 1 to 5, Very Short Answer type questions of one mark each.
(iii) Section B contains question number 6 to 10, Short Answer type I questions of two marks each.
(iv) Section C contains question number 11 to 22, Short Answer type II questions of three marks each.
(v) Section D contains question number 23, Value Based Question of four marks.
(vi) Section E contains question number 24 to 26, Long Answer type questions of five marks each.
(vii) There is no overall choice in the question paper, however, an internal choice is provided in one question of two marks, one question of three marks and all three questions of five marks. An examinee is to attempt any one of the questions out of the two given in the question paper with the same question number.
- Question 1
What does nature's carrying capacity for a species indicate?VIEW SOLUTION
- Question 2
Suggest a molecular diagnostic procedure that detects HIV in a suspected AIDS patient. VIEW SOLUTION
- Question 3
Name two animals that exhibit Oestrus cycle. VIEW SOLUTION
- Question 4
Mention one difference to distinguish an exon from an intron. VIEW SOLUTION
- Question 5
What is a Mutagen? Name a physical factor that can be a Mutagen. VIEW SOLUTION
- Question 6
How e-wastes are being handled in our country? Write the correct solution for treatire this waste. VIEW SOLUTION
- Question 7
Suggest four advanced ex-situ methods to conserve threatened bio-diversity. VIEW SOLUTION
- Question 8
State the role of Oxytocin in parturition. What triggers its release from the pituitary? VIEW SOLUTION
- Question 9
(a) "Fortification of crops is the need of the hour." Give two reasons.
(b) Select one fresh-water and one marine fish from the following:
Prawn; Catla; Mackerel; Lobster VIEW SOLUTION
- Question 10
How does a test cross help to determine the genotype of an individual?
Mention two applications of DNA polymorphism. VIEW SOLUTION
- Question 11
Explain with the help of an example the relationship between restriction endonuclease and a palindromic nucleotide sequence. VIEW SOLUTION
- Question 12
Draw a labelled diagram of the embryonic stage that gets implanted in the human uterus. State the functions of the two parts labelled. VIEW SOLUTION
- Question 13
(a) State Oparin-Haldane's hypothesis.
(b) How does S.L. Miller's experiment supports it? VIEW SOLUTION
- Question 14
(a) Draw a labelled sketch of a mature 7-celled, 8-nucleate embryo-sac.
(b) Which one of the cell in an embryo-sac produce endosperm after double fertilization? VIEW SOLUTION
- Question 15
Narrowly utilitarian arguments are put forth in support of biodiversity conservation.
Mention the other two arguments that are put forth in support of the same cause. VIEW SOLUTION
- Question 16
Draw a pyramid of bio-mass and pyramid of energy in sea. Give your comments on the shape of pyramids drawn.Or
(a) Rearrange the following greenhouse gases in increasing order of their relative contribution to the total global warming.
N2O; CFC; CO2; C2H4.
(b) What is the effect of global warming on polar ice-caps? Comment on its possible ecological impact. VIEW SOLUTION
- Question 17
(a) What is Gene therapy?
(b) Describe the procedure of such a therapy that could be a permanent cure for a disease. Name the disease. VIEW SOLUTION
- Question 18
Human blood group is a good example of multiple allelism and Co-dominance. Justify. VIEW SOLUTION
- Question 19
You make a visit to a Hill station, one of your friend suddenly became unwell and felt uneasy.
(a) list two symptoms you would look for to term it to be due to allergen.
(b) Explain the response of the body to an allergen.
(c) Name two drugs that can be recommended for immediate relief. VIEW SOLUTION
- Question 20
(a) A parasite has to adapt to be able to live in a host. Write the various parasitic adaptations.
(b) Mention an adaptive feature exhibited in brood parasitism in Koel and Crow. VIEW SOLUTION
- Question 21
(a) Why did Hershey and Chase use radioactive sulfur and radioactive phosphorus in their experiment?
(b) Write the conclusion they arrived at and how. VIEW SOLUTION
- Question 22
Why does the 'insertional inactivation' method to detect recombinant DNA is preferred to 'antibiotic resistance' procedure? VIEW SOLUTION
- Question 23
You have a friend whose parents are too indulgent in his/her daily affairs. They think him/her to be still young which makes him/her sad and is upset all the time. As he/she feels that the parents should give him/her opportunity to take independent decision on some issues.
(a) Would you support your friend and why?
(b) Write the characteristics of this age group.
(c) List two curative measures. VIEW SOLUTION
- Question 24
(a) Where does spermatogenesis occur in human testes? Describe the process of spermatogenesis upto the formation of spermatozoa.
(b) Trace the path of spermatozoa from the testes upto the ejaculatory duct only.
Explain the events upto fertilization that occur in a flower after the pollengrain has landed on its compatible stigma. VIEW SOLUTION
- Question 25
(a) How does a Human Immunodeficiency Virus (HIV) replicate in a host?
(b) How does an HIV-infected patient lose immunity?
(c) List any two symptoms of this disease.
Describe the process of waste-water treatment under the following heads :
(a) Primary treatment.
(b) Secondary treatment. VIEW SOLUTION
- Question 26
(a) State the cause and symptoms of colour-blindness in humans.
(b) Statistical data has shown that 8% of the human males are colour-blind when only 0.4% of females are colour-blind. Explain giving reasons how is it so.
(a) Describe Hardy-Weinberg's principle.
(b) How do variation lead to speciation?
(c) How is the genetic equilibrium affected by the variations leading to speciation. VIEW SOLUTION