Sexual Reproduction in Flowering Plants — BIOLOGY STD 12 Science — Question

How has RNAi technique helped to prevent the infestation of roots in tobacco plants by a nematode Meloidogyne incognita?

1. What is green revolution? Mention the steps that led to it.
2. Name the scientist whose contribution led to the development of semi-dwarf wheat varieties in India.

Many plant and animal species are on the verge of their extinction because of loss of forest land by indiscriminate use by the humans. As a biology student what method would you suggest along with its advantages that can protect such threatened species from getting extinct?

Sketch and label reflex arc.

How did the process of RNA interference help to control the nematode from infecting the roots of tobacco plants?
Or
How has RNAi technique helped to prevent the infestation of roots in tobacco plants by a nematode Meloidogyne incognita?

Public all over India is very much concerned about the deteriorating air quality in large parts of North India. Alarmed by this situation the Resident's Welfare Association of your locality organised an awareness programme entitled "Bury not burn'. They invited you, being a biology student to participate.

1. How would you justify your arguments that promote burying and discourage burning? (Give two reasons).
2. With the help of flowcharts, one for each practice, depict the chain of events that follow.

Women are often blamed for producing female children. Consequently, they are ill treated and ostracised. How will you address this issue scientifically if you were to conduct an awareness programme to highlight the values involved?

Explain the role of the enzyme EcoRI in recombinant DNA technology.

What is the major advantage of producing plants by micropropagation?

1. HIV and Hepatitis B are STDs. Mention any two other ways by which they can be transmitted to a healthy person.
2. Why is early detection of STD essential? What can it lead to otherwise?