Human activities interfere with carbon cycle. List any two such activities.
Two human activities that interfere with carbon cycles are
(i) Rapid deforestation and
(ii) Massive burning of fossil fuel for energy and transport.
Flow of energy through various trophic levels in an ecosystem is unidirectional and non-cyclic. Explain.
Flow of energy in an ecosystem is always unidirectional, i.e., energy flow in one way and is noncyclic, like
$$ \underset{\text { Ist Trophic level }}{\text { Plants }} \longrightarrow \underset{\text { Ilnd Trophic level }}{\text { Herbivore }} \longrightarrow \underset{\text { Ill rd Trophic level }}{\text { Carnivore }} \longrightarrow \underset{\text { IVth Trophic level }}{\text { Top carnivore }} $$
As the energy content is decreasing from lst trophic level to next trophic level and so on, thus the energy cannot pass in reverse direction.
Apart from plants and animals, microbes form a permanent biotic component in an ecosystem. While plants have been referred to as autotrophs and animals as heterotrophs. What are microbes referred to as? How do the microbes fulfill their energy requirements?
On the basis of nutrition, organisms are classified as autotrophs and heterotrophs. Autotrophs are further categorised into photoautotrophs and chemoautotrophs, while heterotrophs may be parasite pred or a saprophyte etc.
Microbes are saprotrophs and derive nourishment or energy from dead organic matter or remain of plants and animals and this digestion is extracellular.
Poaching of tiger is a burning issue in today's world. What implication would this activity have on the functioning of the ecosystem of which the tigers are an integral part?
Tiger represents an important part of the food web and helps in maintaining the ecological stability. As a carnivore, it keeps a check on the unlimited growth of herbivoresing the and also removes sick or old animlas from the population. It also acts as an indicator of the forest's health.
Saving the tiger means we save the forest. Since, tiger (top carnivore of the food chain) cannot live in places where trees or herbivores, that it hunts, have vanished and in turn secure food and water for all.
In relation to energy transfer in ecosystem, explain the statement " 10 kg of deer's meat is equivalent to 1 kg of lion's flesh".
In an ecosystem, flow (transfer) of energy is unidirectional. As energy trapped in Ist tropic level, only 10\% of energy is transferred to next trophic level.
