KENDRIYA VIDYALAYA ALIGANJ LUCKNOW
SUMMER VACATION HOME WORK CLASS XII C BIOLOGY 2014-2015
1.
Why is reproduction essential for
organisms?
2.
Which is a better mode of
reproduction sexual or asexual? Why?
3.
Why is the offspring
formed by asexual reproduction referred to as clone?
4.
Offspring formed due to
sexual reproduction have better chances of survival. Why? Is this statement
always true?
5.
How does the progeny
formed from asexual reproduction differ from those formed by sexual
reproduction?
6.
Distinguish between
asexual and sexual reproduction. Why is vegetative reproduction also considered
as a type of asexual reproduction?
7.
Differentiate between
gametogenesis from embryogenesis.
8.
Describe the
post-fertilisation changes in a flower.
9.
What is a bisexual flower?
Collect five bisexual flowers from your neighbourhood find out their common and
scientific names.
10. Examine a few flowers of any cucurbit plant and try to identify
the staminate and pistillate flowers. Do you know any other plant that bears
unisexual flowers?
11. Why are offspring of oviparous animals at a greater risk as
compared to offspring of viviparous animals?
12. What are chasmogamous flowers? Can cross-pollination occur in
cleistogamous flowers? Give reasons for your answer.
13. Mention two strategies evolved to prevent self-pollination in
flowers.
14. What is self-incompatibility? Why does self-pollination not lead
to seed formation in self-incompatible species?
15. What is bagging technique? How is it useful in a plant breeding
programme?
16. What is triple fusion? Where and how does it take place? Name
the nuclei involved in triple fusion.
17. Why do you think the zygote is dormant for sometime in a
fertilized ovule?
18. Make a neat and clean labelled diagram of typical ovule
and monocot seed
19. Why is apple called a false fruit? Which part(s) of the flower
forms the fruit?
20. What is meant by emasculation? When and why does a plant breeder
employ this technique?
21. If one can induce parthenocarpy through the application of
growth substances, which fruits would you select to induce parthenocarpy and
why?
22. Explain the role of tapetum in the formation pollen-grain wall.
23. What is apomixis and what is its importance?
24. What is lactational amenorrhoea
25. Explain the functioning of oral
contraceptive pills
26. Write short notes on (a) ART (b) MTP
27. List common STDs and their causative agents
.How can these be prevented ?
28. Is sex education is necesarry in school ? Why ?
29. Expand following IVF,ZIFT,IUT,GIFT,ICSI,AIT
30. Write short notes on (a) Amniocentesis
(b)Chorionic Villi Sampling
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