PUC Science 2nd PUC Class 12 - Karnataka Board PUC Question Bank Solutions

Where in the fallopian tube does fertilization occur in humans?

Describe the development of a fertilized ovum upto implantation.

Explain divergent evolution with two examples. 

Describe how do 'flocs' and 'activated sludge' help in Sewage Treatment.

Write the role of ‘restriction sites’ in the cloning vector pBR322.

Write the steps you would suggest to be undertaken to obtain a foreign-gene-product.

Public all over India is very much concerned about the deteriorating air quality in large parts of North India. Alarmed by this situation the Resident’s Welfare Association of your locality organized an awareness programme entitled “Bury not burn”. They invited you, being a biology student to participate.

1. How would you justify your arguments that promote burying and discourage burning? (Give two reasons.)
2. With the help of flow charts, one for each practice depicts the chain of events that follow.

How do mycorrhizae help the plants to grow better?  

Name the animals in which methanogens occur and the role they play there.

'in-situ' Conservation can help endangered/threatened species. Justify the statement.

Name and describe any three causes of bio-diversity losses.

Prepare a flow chart in formation of recombinant DNA by the action of restriction endonuclease enzyme EcoRI.

Name the two intermediate hosts which the human liver fluke depends on to complete its life cycle so as to facilitate parasitization of its primary host.

There are many animals that have become extinct in the wild but continue to be maintained in Zoological parks.
(i) What type of biodiversity conservation is observed in this case?
(ii) Explain any other two ways which help in this type of conservation.

What is the mechanism by which the AIDS virus causes deficiency of immune system of the infected person?

How does the application of the fungal genus, Glomus, to the agricultural farm increase the farm output? 

1. What precaution(s) would you recommend to a patient requiring repeated blood transfusion?
2. If the advise is not followed by the patient, there is an apprehension that the patient might contract a disease that would destroy the immune system of his/her body. Explain with the help of schematic diagram only how the immune system would get affected and destroyed.

How does the application of cyanobacteria help improve agricultural output?

Explain the ovarian and uterine events that occur during a menstrual cycle in a human female under the influence of pituitary and ovarian hormones respectively.

Choose the correct answer from the four options given below : 
 On which day of the menstrual cycle does ovulation take place ?