Science (English Medium) कक्षा १२ - CBSE Question Bank Solutions for Biology

Name the states involved in Ganga action plan.

What is the group of bacteria found in both the rumen of cattle and shidge of sewage treatment?

Why are flocs important in biological treatment of waste water?

Why is aerobic degradation more important than anaerobic degradation for the treatment of large volumes of waste waters rich in organic matter. Discuss.

Discuss about the major programs that the Ministry of Environment and Forests, Government of India, has initiated for saving major Indian rivers from pollution.

Ganga has recently been declared the national river. Discuss the implication with respect to pollution of this river.

What would happen if a large volume of untreated sewage is discharged into a river?

In what way anaerobic sludge digestion is important in sewage treatments?

What does ‘competent’ refer to in competent cells used in transformation experiments?

What modification is done on the Ti plasmid of Agrobacterium tumefaciens to convert it into a cloning vector?

A plasmid without a selectable marker was chosen as vector for cloning a gene. How does this affect the experiment?

Describe the role of CaCl₂ in the preparation of competent cells?

Name the regions marked A, B and C.

For selection of recombinants, insertional inactivation of antibiotic marker has been superceded by insertional inactivation of a marker gene coding for a chromogenic substrate. Give reasons.

Describe the role of Agrobacterium tumefaciens in transforming a plant cell.

With respect to understanding diseases, discuss the importance of transgenic animal models.

Name the first transgenic cow. Which gene was introduced in this cow?

Transgenic animals are the animals in which a foreign gene is expressed. Such animals can be used to study the fundamental biological process, phenomenon as well as for producing products useful for mankind. Give one example for each type.

Define transgenic animals. Explain in detail any four areas where they can be utilised.

Productivity is the rate of production of biomass expressed in terms of ______.