Science (English Medium) इयत्ता १२ - CBSE Important Questions for Biology

Give the applications of DNA fingerprinting technique.

What is biopiracy?

Name any two biodiversity hot spots in India.

Differentiate between Parthenocarpy and Parthenogenesis. Give one example of each.

Differentiate between Parthenocarpy and Parthenogenesis. Give one example of each.

Describe any two devices in a flowering plant which prevent both autogamy and geitonogamy.

Describe any two devices in a flowering plant which prevent both autogamy and geitonogamy.

Draw a diagram of the microscopic structure of human sperm. Label the following parts in it and write their functions

(a) Acrosome

(b) Nucleus

(c) Middle piece

Medically it is advised to all young mothers that breastfeeding is the best for their newborn babies. Do you agree? Give reasons in support of your answer.

Explain menstrual cycle in human females.

How can the scientific understanding of the menstrual cycle of human females help as a contraceptive measure?

How did a citizen group called Friends of Arcata Marsh Arcata, California, USA, help to improve the water quality of the marshland using Integrated Waste Water Treatment? Explain in four steps.

Explain the mechanism of 'sex determination' in birds. How does it differ from that of human beings?

Looking at the deteriorating air quality because of air pollution in many cities of the country, the citizens are very much worried and concerned about their health. The doctors have declared the health emergency in the cities where the air quality is very severely poor.

1) Mention any two major causes of air pollution.

2) Write any two harmful effects of air pollution to plants and humans.

3) As a captain of your school Eco-club, suggest any two programmes you would plan to organise in the school so as to bring awareness among the students on how to check air pollution in and around the school.

Write the scientific name of the organism Thomas Hunt Morgan and his colleagues worked with for their experiments. Explain the correlation between linkage and recombination with respect to genes as studied by them.

How did Sturtevant explain gene mapping while working with Morgan?

Write the dual purpose served by Deoxyribonucleoside triphosphates in the polymerisation.

Expand VNTR and describe its role in DNA fingerprinting.

State the 'Central dogma' as proposed by Francis Crick. Are there any exceptions to it? Support your answer with a reason and an example.

Explain how the biochemical characterisation (nature) of 'Transforming Principle' was determined, which was not defined from Griffth's experiments.