Class 12th Biology 2017 Set1 Outside Delhi Board Paper Solution
Suggest two practices giving one example each, that help protect rare or threatened species.
1) Ex-situ conservation: Gene Bank
By using cryopreservation (preservation at –196ºC) technique, sperms, eggs, tissues, and embryo can be stored for long period in gene banks, seed banks etc
2) In-situ conservation: Biosphere reserve, wildlife santuaries, national parks.
Popular Questions of Class 12th biology
- Q:- What is spermatogenesis? Briefly describe the process of spermatogenesis.
- Q:- Why is reproduction essential for organisms? Answer
- Q:- Write a short note on
(a) Adaptations of desert plants and animals
(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.
- Q:- What is DNA fingerprinting? Mention its application.
- Q:- Describe the structure of a seminiferous tubule.
- Q:- What is oogenesis? Give a brief account of oogenesis.
- Q:- What is triple fusion? Where and how does it take place? Name the nuclei involved in triple fusion.
- 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
- Q:- Do you think that reproductive health in our country has improved in the past 50 years? If yes, mention some such areas of improvement.
- Q:- Differentiate between gametogenesis from embryogenesis.
- Q:- Define ecological pyramids and describe with examples, pyramids of number and biomass.
- Q:- Suggest some methods to assist infertile couples to have children.
- Q:- Explain why meiosis and gametogenesis are always interlinked?
- 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.
(k) The structure which provides vascular connection between fetus and uterus is called ____________. - Q:- How do ecologists estimate the total number of species present in the world?
- Q:- Besides better aeration and mixing properties, what other advantages do stirred tank bioreactors have over shake flasks?
- Q:- What would be the molar concentration of human DNA in a human cell? Consult your teacher.
- Q:- Which is a better mode of reproduction sexual or asexual? Why?