Energy and Life Case Study

Energy is defined as the ability

to do work; all living things

require some level of energy

to keep them alive. The source

of energy is from the sun as

we are part of the solar

system. Living things have

different abilities in using this

energy in what is known as

metabolism activity. This

represents a sum of all

chemical reactions that take

place in living organisms and

result in the energy process. This energy can be used for all

different activities including growth, movements, and

respiration.

Metabolism is composed of catabolic and anabolic reactions.

Catabolic means the breakdown of macromolecules into

basic building blocks. Anabolic means using the materials

that resulted from the breakdown to rebuild the new

structures.

Living things are divided regarding metabolism into different

categories:

1. Autotroph – represents those organisms that can

produce their own food, because; they have the ability

to perform photosynthesis capturing the sunlight and

converted into stored chemical energy in food.

2. Heterotroph – organisms that can’t make photosynthesis

and depend on produced foods.

3. Decomposers – the last group that is responsible to

recycle all the materials.

The energy level is conserved between these three levels of

living organisms.