MODEL SUBJECTIVE QUESTIONS:
- What is ecosystem? Give its components.
- Give physiognomic characteristics.
- Write note on ecological energetics.
- Write note food chain, food web and trophic levels.
- Write note on ecological pyramids.
- Describe nitrogen cycle.
- Describe hydrological cycle.
1. What are consumers?
Ans: They are the living organisms that utilize or decompose the complex material synthesized by the producers. The heterotrophs,. do not produce their own food. They depend on other autotrophic organisms for their nourishment.
- What primary consumers? Give their examples.
Ans: They are purely herbivorous animals. They include large animals or macroconsumers like many insects, mouse, rabbits, goat sheep, deer, birds etc. These are the common herbivorous of terrestrial ecosystem. Protozoa small molluscs and Crustaceans and fishes are herbivores of the aquatic ecosystem.
- What are Tertiary Consumers or top consumers?
Ans: They eat the herbivores, carnivores and omnivores for their energy. Tertiary consumers include lion, tiger, hawk etc.
- What are artificial ecosystems?
Ans: In these types of Ecosystem. natural balance is disturbed by man and balance is maintained by him. Artificial ecosystem consists of man made forest, orchards, cultivated fields etc.
- Differentiate between gross and net primary productivity. Ans: The total rate of photosynthesis or the total amount of organic matter fixed is called gross primary productivity. The organic matter stored in plant tissues is called net primary productivity.
- What is food chain? Give example.
Ans: The sequence of organisms through which energy moves in an ecosystem is called food chain. For example, plains are eaten by herbivores. The herbivores are eaten by carnivores. Thus the food manufactured by plants travel from producers to herbivores and herbivores to•camivores.
- What is Saprophytic or Detritus Food Chain?
Ans: It is a type of food chain in wlich decomposers like fungi and bacteria attack dead remains cf plants and animals to obtain food.
- What are ecological pyramids?
Ans: The representations of flow of eneug. through an ecosystem in the form of pyramids are called ecoloE cal pyramids.
- What are pyramids of numbers?
Ans: The pyramid which shows the relationship between the number of producers, herbivores and carnivores at successive trophic levels is called pyramid of numbers.
- Give pyramids forest or savanna ecosystem.
Ans: The number of producers like herbs, shrubs and trees are in large number than the number of herbivores like deer, antelopes, elephants, zebra, giraffe. The number of carnivore like lion and tiger are far less in number as compared to the herbivore.
- What are pyramids of biomass?
Ans: The pyramid which shows the relationship between the biomass of producers, herbivores and carnivores at successive trophic levels is called pyramid of biomass.
- Define biogeochemical cycle.
Ans: The cyclic exchange of different chemical elements between the living and non-living component of the biosphere is called biogeochemical cycle.
- What is ammonification?
Ans: The breakdown of nitrogenous compound like protein, amino acids into ammonia with the help of micro-organism like fungi and bacteria is called ammonification.