Photosynthesis, Respiration And Energy Relationships Essay, Research Paper

State that light is the initial energy source for almost all

communities State that the carbon dioxide fixed by photosynthesis is released by

respiration State that the energy released during breakdown/respiration of complex

compounds in an organism is used to do work or is lost as heat Define biomass The total mass of organic matter in organisms or ecosystems. Water is not

organic matter and so is not included. Explain biomass and energy transfer in a food chain in terms of growth,

respiration, cell activities, and waste State that when energy transformations take place, including those in living

organisms, the process is never 100% efficient, commonly being 10-20% Explain what is meant by a pyramid of energy and reasons for its shape Energy is lost in several ways as it flows along these pathways of

consumption. Most plant tissue is uneaten by herbivores, and this stored energy

is therefore lost to the plant-herbivore-carnivore food chain. In terrestrial

communities less than 10 percent of plant tissue is actually consumed by

herbivores. The rest falls into the detritus pathway, although the detritivores

consume only some of this decaying tissue. Oil and coal deposits are major

repositories of this unused plant energy and have accumulated over long periods

of geologic time. Design a pyramid of energy given appropriate information | Foxes ||||||| Rabbits |||||||||||||||| Grasses Explain that energy enters and leaves an ecosystem, but nutrients must be

recycled. Heat energy is lost and dissipated into the environment. Because of this, it

flows in one direction only. Like energy, minerals such as carbon, nitrogen and

phosphorus exist in different forms. Unlike energy, these forms can be

continuously recycled and so used repeatedly by organisms. Most have a

geological and a biological component. The former is the long-term reservoir,

while the latter is the short term recycling method. Draw the carbon cycle to show the processes including photosynthesis,

respiration, combustion, and fossilisation. Explain the role of Saprotrophs (decomposers) in returning elements to the

environment in inorganic form. The final link in all food chains is made up of decomposers, those

heterotrophs that break down dead organisms and organic wastes. A food chain in

which the primary consumer feeds on living plants is called a grazing pathway;

that in which the primary consumer feeds on dead plant matter is known as a

detritus pathway. Both pathways are important in accounting for the energy

budget of the ecosystem.