Energy and Life
Energy and Life
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.
Homeostasis
Homeostasis is a very
important concept of life, this
means staying within a level
of constant (staying the
same). Living things are part
of the ecosystem and that
means they have some kind of
interactions and changes, they
will never stay exact at all
times. This mechanism allows
them to adjust and come back
to the previous point. The
changes represent internal
and external causes that if not correct will cause harm to
the organs.
Homeostasis is a mechanism that has several components
to be functional.
First, it required a cause which is called a stimulation such
as a temperature or level of glucose in the blood, this has to
be detected by receptors and reported to a control center in
the nervous system where the information will be processed
and a design will be established and the order is carried to
target or effectors how will respond and make the
adjustments such as sweating.
Let us look at the example of temperature. If you stand
outdoors and the weather temperature is 105, heat will start
to go into your body if this continues your internal
temperature will be equal to the environment, this does not
happen because receptors in your skin detect this and
report to the hypothalamus, the hypothalamus sends orders
to targets, as a result, you will notice increase heart rate,
increase respiration, increase urination, and sweating this
will keep your body temperature the same. This is known as
the negative feedback loop, homeostasis also uses a
positive feedback loop in some conditions such as childbirth.
