PUC Science 2nd PUC Class 12 - Karnataka Board PUC Important Questions for Biology

A group of youth were having a ‘rave party’ in an isolated area and was raided by police. Packets of ‘smack’ and syringes with needles were found littered around.

1. Why is taking ‘smack’ considered an abuse?
2. Write the chemical name of ‘smack’ and the name of its source plant.
3. Syringes and needles used by the youth for taking the drug could prove to be very fatal. Why?

You have attended a birthday party hosted by one of your classmates. You found some guests at the party sitting in a corner making a lot of noise and consuming 'something'. After a while one of the boys from the group started screaming, behaving abnormally and sweating profusely. On enquiry you found that the group members were taking drugs.

(a) Would you inform your parents/school authorities ? Yes/No. Give reasons in support of your answer.

(b) Prepare a note to be circulated amongst the schoolmates about the sources and dangers of any two drugs.

(c) Write any two ways that you will suggest to your school principal so as to promote awareness amongst the youth against the use of these drugs.

Under polio prevention programme, infants in India were given polio vaccines on a large scale at regular intervals to eradicate polio from the country.

(a) What is a vaccine? Explain how does it impart immunity to the child against the disease.
(b) With the help of an example each, differentiate between active and passive immunity.

Which one of the following is the most accurate definition of the term ‘health’?

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

By taking two examples explain how has bio-fortification helped in improving food quality.

How does the application of cyanobacteria help improve agricultural output?

"Man can be a primary as well as a secondary consumer." Justify this statement.

Bottled fruit juices are clearer as compared to those made at home. Explain.

What is gene therapy? Name the first clinical case in which it was used.

Why does Bt toxin not kill the bacterium that produces it, but kill the insect that ingests it?

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

One of the major contributions of biotechnology is to develop pest-resistant varieties of cotton plants. Explain how it has been made possible.

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

How do mycorrhizae help the plants to grow better?  

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.