Energy Cycle in Living Things The chloroplasts collect energy from the sun and use carbon dioxide and water in the process called photosynthesis to produce sugars. The energy cycle for life is fueled by the Sun. The main end product for plants and animals is the production of highly energetic molecules like ATP .

The flow of energy is always unidirectional. The energy passes from primary producers to primary consumers. From the primary consumers, the energy is passed to secondary consumers and then to tertiary consumers.

The energy is used to continue life’s processes (i.e. reproduction, growth, etc.) while the matter is used to build and rebuild structure. cavengers and decomposers. These organisms break down dead matter to return it to the soil for use by producers so that the cycle can begin again.

Rejected energy is part of the energy of a fuel – such as gas or petrol – that could be used for a purposeful activity, like making electricity or transport. For a coal fired power station, for instance, about 2/3 of the energy released when the coal is burnt is discarded as heat in the environment.

The information we get are: i The energy flow is unidirectional it flows from sun → autotrophs → herbivores → carnivores → decomposers ii The flow of energy is 10% i.e. 90% of the energy is used by a given level of food chain for metabolic activities.

Humans influence energy flow and are modifying the energy balance of Earth’s ecosystems at an increasing rate. Changes in the availability of energy affect ecosystems. When humans modify the energy balance, we impact the ability of the ecosystems to react and adapt to variability in the environment.

Humans impact the physical environment in many ways: overpopulation, pollution, burning fossil fuels, and deforestation. Changes like these have triggered climate change, soil erosion, poor air quality, and undrinkable water.

generation of electricity (e.g., burning of coal, natural gas); use of refrigerants and coolants (ozone-depleting substances); metal smelting and other industrial activities (e.g., pulp and paper, chemical manufacturing, and other heavy industries);

Land-use change: Humans may destroy natural landscapes as they mine resources and urbanize areas. This is detrimental, as it displaces residing species, reducing available habitats and food sources. This can negatively effect an ecosystem because the introduced species may outcompete native organisms and displace them.