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

What are transgenic bacteria?

Distinguish between primary and secondary productivity.

What is primary productivity?

How is biodiversity important for ecosystem functioning?

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

Mention any four special adaptive evolved in parasites for their parasite mode of life.

Why does primary productivity vary in different types of ecosystems?

State the relation between gross and net primary productivity.

Why is the coding sequence of an enzyme β-galactosidase a preferred selectable marker in comparison to the ones named above?

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

What is ‘Ori’ ? State its importance during cloning of a vector.

Explain the importance of ‘Selectable marker’, with the help of a suitable example.

What is the primary productivity of an ecosystem and how is it expressed?

Explain what does the equation given below show :
NPP = GPP – R

How would you find out whether a given tall garden pea plant is homozygous or heterzygous? Substantiate your answer with the help fo Punnett squares.

Given below are the F₂ – phenotypic ratios of two independently carried monohybrid crosses :
(i) 1 : 2 : 1
(ii) 3 : 1
Mention what does each ratio suggest.

Answer the following question.
What are ‘flocs’, formed during secondary treatment of sewage?

Answer the following question.
Write the basis on which Alfred Sturtevant explained gene mapping.

Answer the following question.
What are 'flocs', formed during secondary treatment of sewage?

Answer the following question.
β galactosidase enzyme is considered a better selectable marker. Justify the statement.