Strategies for Enhancement in Food Reproduction — BIOLOGY STD 12 Science — Question

What is the use of aeration tank in the treatment of sewage?

Mention the name of the causal organism, symptoms and the mode of transmission of the disease Amoebiasis.

Palaeontological evidence support the theory of organic evolution. Explain with an example.

What do you understand by the term biopesticide? Name and explain the mode of action of a popular biopesticide. Biopesticides are methods of controlling pests that rely on natural predation rather than introduced chemicals/ or living organisms used to kill pests.

Describe the various types of age pyramids.

Since the origin of life on the earth, there were five episodes of mass extinction of species.

1. How is the 'Sixth Extinction', presently in progress, different from the previous episodes?
2. Who is mainly responsible for the 'Sixth Extinction'?
3. List any four points that can help to overcome this disaster.

Amniocentesis for sex determination is banned in our country. Is this ban necessary? Comment

On world population day, Rohit and his friends arranged an awareness campaign on population explosion programme in their locality. Some elderly people tried to stop the children and asked them not to talk on such things in public. The children convinced the elders about the need for the programme and on understanding their point of view, the elders also joined the campaign.

1. Why is such awareness programme necessary?
2. What role has the government played in controlling population explosion?
3. When were reproductive health programmes initiated in India?
4. What values did Rohit and his friends show on the occasion?

What will happen to an ecosystem if:
All producers are removed.

How many primary follicles are left in each ovary in a human female at puberty?