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

Answer the following question.
Expand ‘YAC’ and mention what it was used for.

Answer the following question.
Secondary treatment of the sewage is also called Biological treatment. Justify this statement and explain the process.

Answer the following question.
Describe the inter-relationship between productivity, gross primary productivity, and net productivity.

"Artificial insemination helps overcome several problems of normal mating in cattle". Do you agree? Support your answer with any three reasons.

Write the relationship between productivity, gross primary productivity, net primary productivity, and secondary productivity.

How does the β-galactosidase coding sequence act as a selectable marker? Why is it a preferred selectable marker to antibiotic resistance genes? Explain.

Name the tank to which the sewage water is passed after the preliminary treatment?

During microsporogenesis, meiosis occurs in ______.

A patient admitted in ICU was diagnosed to have suffered from myocardial infarction. The condition of coronary artery is depicted in the image below.

Name two bioactive agents and their mode of action that can improve this condition.

α - 1 antitrypsin is ______.

How much of the net primary productively of a terrestrial ecosystem is eaten and digested by herbivores?

Indicate the stages where meiosis and mitosis occur (1, 2 or 3) in the flow chart.

In a monohybrid cross of plants with red and white flowered plants, Mendel got only red-flowered plants. On self-pollinating these F1 plants got both red and white flowered plants in 3:1 ratio. Explain the basis of using RR and rr symbols to represent the genotype of plants of parental generation.

In a plant tallness is dominant over dwarfness and red flower is dominant over white. Starting with the parents work out a dihybrid cross. What is standard dihybrid ratio? Do you think the values would deviate if the two genes in question are interacting with each other?

Wastewater treatment generates a large quantity of sludge, which can be treated by ______.

The primary treatment of waste water involves the removal of ______.

BOD of waste water is estimated by measuring the amount of ______.

What would happen if oxygen availability to activated sludge flocs is reduced?

Activated sludge should have the ability to settle quickly so that it can ______.

Why do we prefer to call secondary waste water treatment as biological treatment?