Class 12th Biology 2017 Set1 Outside Delhi Board Paper Solution
Mention one application for each of the following:
1 Passive immunization
2 Antihistamine
3 Colostrum
4 Cytokinin-barrier
1 Passive immunization: In the case of snakebites, the injection which is given to the patients contain performed antibodies against the snake venom.
Passive immunisation provides quick immune response in the body.
2 Antihistamine: It is a pharmaceutical drug that opposes the activity of histamine reception in the body.
3 Colostrum: The yellowish fluid colostrum secreted by mother the initial days of lactation has abundant antibodies(IgA) to protect the infant.
4 Cytokinin-barrier: Virus infected cells secrete proteins called interferons which protect non-infected cells from further viral infection.
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- Q:-
Fill in the blanks:
(a) Humans reproduce __________. (asexually/sexually)
(b) Humans are__________. (oviparous/viviparous/ovoviviparous)
(c) Fertilization is __________ in humans. (external/internal)
(d) Male and female gametes are __________. (diploid/haploid)
(e) Zygote is __________. (diploid/haploid)
(f) The process of release of the ovum from a mature follicle is called__________.
(g) Ovulation is induced by a hormone called the __________.
(h) The fusion of male and female gametes is called _____________.
(i) Fertilisation takes place in _____________.
(j) Zygote divides to form _____________which is implanted in uterus.
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