Class 12th Biology 2013 Set3 Delhi Board Paper Solution
Question 10
Why the pyramid of energy is always upright? Explain.
Answer
Pyramid of energy is upright because when energy flows from a trophic level to next trophic level, some energy is always lost as heat at each step. Finally it is lost to atmosphere and never goes back to Sun.
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:- What is DNA fingerprinting? Mention its application.
- Q:- Define decomposition and describe the processes and products of decomposition.
- Q:- Differentiate between gametogenesis from embryogenesis.
- Q:- Fill in the blanks.
(a) Plants are called as_________ because they fix carbon dioxide.
(b) In an ecosystem dominated by trees, the pyramid (of numbers) is _________ type.
(c) In aquatic ecosystems, the limiting factor for the productivity is _________.
(d) Common detritivores in our ecosystem are_________.
(e) The major reservoir of carbon on earth is_________. - Q:-
Secondary producers are
(a) Herbivores
(b) Producers
(c) Carnivores
(d) None of the above - Q:- Name the primary and secondary lymphoid organs.
- Q:- What is point mutation? Give one example.
- Q:- What is primary productivity? Give brief description of factors that affect primary productivity.
- Q:- What is vegetative propagation? Give two suitable examples.
- Q:- How does the progeny formed from asexual reproduction differ from those formed by sexual reproduction?