| Class XII |
Biology |
Biology |
11 |
parasites have evolved to be host-specific (they can parasitise only a single species of host) in such a way that both host and the parasite tend t... |
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| Class XII |
Biology |
Biology |
11 |
cells, etc.). The life cycles of endoparasites are more complex because of their extreme specialisation. Their morphological and anatomical feature... |
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| Class XII |
Biology |
Biology |
11 |
is pollinated by wasp; (b) Wasp laying eggs in a fig fruit (v) Mutualism: Thisinteractionconfersbenefitsonboththeinteracting species. Lichens repre... |
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| Class XII |
Biology |
Biology |
11 |
deceit’ to get pollination done by a species of bee. One petal of its flower bears an uncanny resemblance to the female of the bee in size, colour ... |
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| Class XII |
Biotechnology |
Biotechnology |
1 |
are true and the reason is the correct explanation of the assertion. (b) Both assertion and reason are true but the reason is not the correct expla... |
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| Class XII |
Biology |
Biology |
11 |
through births and immigration and decline through deaths and emigration. When resources are unlimited, the growth is usually exponential but when ... |
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| Class XII |
Biology |
Biology |
11 |
terms and give one example for each: (a) Commensalism (b) Parasitism (c) Camouflage (d) Mutualism (e) Interspecific competition 8. With the help of... |
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| Class XII |
Biology |
Biology |
12 |
CHAPTER 12 ECOSYSTEM 12.1 Ecosystem–Structure andFunction An ecosystem can be visualised as a functional unit of 12.2. Productivity nature,whereliv... |
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| Class XII |
Biology |
Biology |
12 |
occupying different levels is called stratification. For example, trees occupy top verticalstrataorlayerofaforest,shrubsthesecondandherbsandgrasses... |
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| Class XII |
Biology |
Biology |
12 |
(kcal m ). The rate of biomass production is called productivity. –2 –1 – –1 It is expressed in terms of gm yr or (kcal m ) yr to compare the produ... |
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| Class XII |
Biology |
Biology |
12 |
raw material for decomposition. The important steps in the process of decomposition are fragmentation, leaching, catabolism, humification and miner... |
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| Class XII |
Biology |
Biology |
12 |
energy captured by plants flows through different organisms of an ecosystem.Allorganismsaredependentfortheirfoodonproducers,either directly or indi... |
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| Class XII |
Biology |
Biology |
12 |
A simple grazing food chain (GFC) is depicted below: Grass Goat Man (Producer) (Primary Consumer) (Secondary consumer) Reprint 2026-27 BIOLOGY The ... |
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| Class XII |
Biology |
Biology |
12 |
a certain mass of living material at a particular time called as the standing crop. The standing crop is measured as the mass of living organisms (... |
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| Class XII |
Computer Science |
Computer Science |
9 |
specifies the type of data that an attribute can hold. StructuredQueryLanguage(SQL) Reprint 2026-27 • Constraint indicates the restrictions imposed... |
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| Class XII |
Biology |
Biology |
12 |
inverted, because when energy flows from a particular trophic level to the next trophic level, some energy is always lost as heat at each step. Eac... |
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| Class XII |
Biology |
Biology |
12 |
decomposers. Decomposition involves three processes, namely fragmentation of detritus, leaching and catabolism. Energy flow is unidirectional. Firs... |
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| Class XII |
Biology |
Biology |
12 |
the components of an ecosystem. 8. Define ecological pyramids and describe with examples, pyramids of number and biomass. 9. What is primary produc... |
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| Class XII |
Biology |
Biology |
13 |
CHAPTER 13 BIODIVERSITY AND CONSERVATION 13.1 Biodiversity If an alien from a distant galaxy were to visit our planet 13.2 Biodiversity Conservatio... |
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| Class XII |
Biology |
Biology |
13 |
deserts, rain forests, mangroves, coral reefs, wetlands, estuaries, and alpine meadows has a greater ecosystem diversity than a Scandinavian countr... |
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| Class XII |
Biology |
Biology |
13 |
about 7 million. Reprint 2026-27 BIOLOGY Letuslookatsomeinterestingaspectsaboutearth’sbiodiversitybased on the currently available species inventor... |
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| Class XII |
Biology |
Biology |
13 |
figures, we estimate that there are probably more than 1,00,000 plant species and more than 3,00,000 animal species yet to be discovered and descri... |
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| Class XII |
Biology |
Biology |
13 |
about tropics that might account for their greater 219 biological diversity? Ecologists and evolutionary biologists have proposedvarioushypotheses;... |
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| Class XII |
Biology |
Biology |
13 |
tropical forests of different continents, the slope is found to be 1.15. What do steeper slopes mean in this context? 220 13.1.3 The importance of ... |
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| Class XII |
Biology |
Biology |
13 |
Paul Ehrlich. In an airplane (ecosystem) all parts are joined together using thousands of rivets (species). If every passenger travelling in it sta... |
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