Class 12th Biology 2014 Set1 Delhi Board Paper Solution
Question 3
Name any two types of cells that act as 'cellular barriers' to provide innate immunity in humans.
Answer
Leukocytes (WBC) and natural killer in the blood are two types of cells that act as 'cellular barriers' to provide innate immunity in humans.
Popular Questions of Class 12th biology
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(b) Adaptations of plants to water scarcity
(c) Behavioural adaptations in animals
(d) Importance of light to plants
(e) Effect of temperature or water scarcity and the adaptations of animals. - Q:- With a neat diagram explain the 7-celled, 8-nucleate nature of the female gametophyte.
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- Q:- With a neat, labelled diagram, describe the parts of a typical angiosperm ovule.
- Q:- Explain the Law of Dominance using a monohybrid cross.
Recently Viewed Questions of Class 12th biology
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(a) Dominance and Recessive
(b) Homozygous and Heterozygous
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- Q:- In our society the women are often blamed for giving birth to daughters.
Can you explain why this is not correct? - Q:- Give three hypotheses for explaining why tropics show greatest levels of species richness.
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5-ATGCATGCATGCATGCATGCATGCATGC-3
Write down the sequence of complementary strand in 5→3 direction