The human essential
state, is studied in this paper with relativity to the First and Second Laws of
Thermodynamics whereby the basic metabolic rate and its contrast to the exergy
loss and the dissipation function and the Ultraviolet radiation (UVR)
significant impact on human skin. The studies signify the effects of the blood
flow on the heat balance in a human body and its relationship between the
metabolic rate and the blood perfusion. The analysis also demonstrates the
major environmental factor for skin cancer formation caused by sunburn.
is the set of life-sustaining chemical transformations within the cells of
living things. The three main purposes of metabolism are the conversion of food
to energy to run cellular processes, the conversion of food for the productions
of proteins, lipids, nucleic acids, and carbohydrates, and to eliminate waste
from the body. These enzyme-catalyzed reactions allow organisms to grow and
reproduce, maintain their structures, and respond to their environments. The
word metabolism can also be use to refer to the sum of all chemical reactions
that occur in living organisms, including digestion and the movements of
substances between two different cells.
is a form of burn that is caused by radiation from the Sun that affects living
tissue especially skin, which results from an overexposure to ultraviolet (UV)
radiation. The general symptoms in humans include reddish skin that is
sensitive to the touch, discomfort, tiredness, and mild dizziness. An excess of
UV radiation may leads to life-threatening skin cancer in extreme cases.
3.0 HUMAN METABOLISM
Metabolic reactions that take place
within our body can be categorized as anabolic and catabolic reactions.
Anabolic reactions consume energy to combine different molecules whereas
catabolic reactions release energy while splitting molecules apart. The energy
stored in ATP created by catabolic reactions is the fuel for anabolic reactions
which synthesize hormones, enzymes, sugars and other substances for cell
growth, reproduction, and tissue repair.
chemical reactions of metabolism are arranged into metabolic pathways, in which
one chemical is transformed through a series of steps into another chemical, by
a sequence of enzymes. Enzymes act as catalysts that allow the reactions to
occurs more rapidly. The metabolic system of a particular organism determines
which substances that is beneficial and harmful to the body. The speed of
metabolism, the metabolic rate, influences how much food an organism will
require, and also affects how it is able to obtain that food.
When we eat our food, the food in our mouth is chewed
and broke to a smaller particle and our digestive system detect the presence of
the food will secrete saliva into our mouth. Saliva play an importance role as
it act as lubricant and moisten the food so that it easily be chewed and shaped
into ball shape so that the food easily be swallowed. The presences of a
digestive enzyme which known as the amylase in the saliva will start the
chemical reaction of starches begin.
After the food arrives at the
stomach, another process happened to break down to smaller particle so that it is
easy for our body to absorb the nutrient and convert it to energy. Besides, the
stomach releases acid and enzymes to help our body break down the food. For an
example, pepsin enzymes break down protein. Both
physical and chemical digestion occurs within the stomach. The continual
churning movements of the muscular walls of the stomach mix food with a
digestive fluid, known as gastric juice. A
structure at the bottom of the stomach known as the pyloric sphincter controls the entry of
chyme into the first part of the small
intestine, called the duodenum.
Ducts from the gall bladder and pancreas feed
fluids rich in bile salts and digestive enzymes into the duodenum. In addition,
some of the cells lining the small intestine produce a fluid known as ‘succus entericus’ made up mostly of water,
mucus and sodium bicarbonate.
Collectively, these fluids
help to lubricate the partially digested food as it moves down the gut,
neutralise the acidic chyme, emulsify fats
and oils and enzymatically digest the protein, carbohydrate and fatty acids present. This
breaking down of large molecules into small molecules is essential as it
enables the absorption of these smaller molecules into the bloodstream.
3.2 FOOD ABSORPTION IN THE SMALL
intestine is the location in the body where the majority of the nutrients from
ingested food are absorbed. Whereas the stomach is responsible for the churning
and mechanical breakdown of food, the small intestine is very important for
absorption. Digested food passes through the wall of the intestine into the
blood vessels which then distribute the nutrition first to the liver and then through the rest of the
This is to show us how food is break
down to smaller particle so that our small intestine can easily absorb to the
blood stream and to muscle as fuel. As we know food contain chemical energy
which then we transform it into mechanical energy at our stomach or muscle.
Thus, there is work done. Then mechanical energy transforms the energy to
Thermal energy=Heat energy
That is why when we doing a lot of
work done, our body produced a lot of heat energy and sweats. For a person that
did not doing a lot of work done, some part of the energy (excess energy) will
be stored up in fat below our skin. For this process, our body (pancreas) will
secrete insulin as enzymes to convert fatty acid and glycerol into fat again.
So when we need more energy for physical activity, our body will convert that
fat into fatty acid and glycerol again for tissue absorption.
THERMAL ENERGY PRODUCED IN OUR BODY
as there is work done, there will be heat energy produced. For human (warmed
blooded animal), we used this heat energy that is by product of our bodies to
kept ourselves in optimum temperature. The chemical energy in our food is
converted to chemical energy in other forms, primarily the compound adenosine
triphosphate. The adenosine triphosphate molecules are then used to power
various cellular processes, including muscle contractions. In the process, each
molecule of adenosine triphosphate is broken down into adenosine diphosphate,
which is later regenerated to adenosine triphosphate again when more food is
A lot of heat is also released during
this process. 37
our body optimum temperature. So when we are doing heavy task such as running,
cycling or exercising, our body produced a lot of excess heat. To keep our
bodies in an optimum temperature, our body temperature regulation mechanism
(Thermoregulation) will be stimulated to get rid of the excess heat so that our
body temperatures return to optimum temperature (37
C). Body heat is generated mostly in the deep organs,
especially the liver, brain, and heart, and in contraction of skeletal muscles.
In sport, our body doing a lot of muscle contraction which generated a lot of
heat by product. There are four avenues of heat loss: convection, conduction,
radiation, and evaporation. If skin temperature is greater than that of the
surroundings, the body can lose heat by radiation and conduction. There are a
few way our body thermoregulations get rid of the excess heat; sweat secreted
by sweat gland and skin blood vessel dilation.
When the body
temperature rises, the blood vessel dilate (Vasodilation) which help our body
get rid of excess heat in two ways. First one is when the blood vessel dilate,
it increase in diameter which make it wider and more blood can flow through it.
The more blood circulate through the blood vessel mean that the higher
efficiency heat loss to the environment surrounding. Second one is when the blood vessel dilate,
it get more nearer to the skin surface thus the heat inside our body get more
easily diffused out to the environment.
Sweat is make of
water from our body. As we all know, water is a universal medium and a very
good heat conductor. So when our body produced a lot of excess heat, the excess
heat will diffused to the water particles inside our body and collected to the
sweat glands and secreted through the sweat pore to the skin surface. This
method is the most effective way to eliminate the excess heat. But this method
caused our body loss a lot of water if it continues a long time which will lead
to low concentration of water fluid in our body cell. Thus when we are doing burdensome
activity, we need to make sure to drink water to keep our body water level
Sunburns is different from thermal burns, which result
from infrared radiation. Infrared radiation provides sunlight its warmth; it is
not the heat of the sun that burns the skin. A sunburn manifested by cutaneous
redness, swelling and pains caused by exposure to the sun’s ultraviolet
radiation, UVA and UVB.
Ultraviolet (UV) is an electromagnetic
radiation with wavelength from
10 nm to 400 nm, shorter than that of visible light.
UV radiation constitutes about 10% of the total light output of the Sun, and is
thus present in sunlight. These wavelengths are classified as UVA,
UVB, or UVC, with UVA the longest of the three at 320-400 nanometers. UVB
ranges from 290 to 320 nm. The shortest wavelength among them is UVC and most
UVC is absorbed by the ozone layer and does not reach the earth.
However, both UVA and UVB penetrate the atmosphere and
play an important role in skin conditions such as premature skin aging, eye
damage, and mostly sunburn. They also suppress the immune system, reducing your
ability to fight off these and other maladies.
The energy from ultraviolet radiation can damage
molecules in the skin, specifically DNA. The effect of this is the synthesis of
different proteins and enzymes. The effects of these proteins, prostaglandins
and cytokines, lead to dilation of the cutaneous blood vessels and a
accumulation of inflammatory cells. This results to redness, swelling and pain.
When the skin is exposed to excessive radiation exposure, it generally takes
four to six hours for these proteins to generate. The body does have mechanisms
to repair damaged DNA after ultraviolet exposure. But as the frequency of
sunlight exposure increases, the probability of some of damage will not be
repair. This mutated DNA may eventually lead to skin cancer.
The two major wavelengths which damages the skin:
UVA, which penetrates the skin more deeply than
UVB, play a major part in skin aging, but recently scientists believed it did
not cause significant damage in the epidermis which is outermost skin layer
where most skin cancers occur. This wavelength, however, started the process of
UVB, the main cause of skin reddening and
sunburn, tends to damage the skin’s more superficial epidermal layers. It plays
a key role in the development of skin cancer and a contributory role in tanning
and photoaging. Its intensity varies by season, location, and time of day.
4.1 HOW SUNBURN OCCURS
The damage is recognized by the body, which then
triggers several defence mechanisms, including protein to revert the damage and
peeling to remove damaged skin cells, and increased melanin production to
prevent future damage. Melanin absorbs UV wavelength light, acting as a thin
bulletproof vest from the a bombard of UV. By preventing UV photons from
disrupting chemical bonds, melanin alters the DNA and the generation of mutated
Sunburn causes an inflammation process,
that started the production of prostanoids and bradykinin. These
chemical compounds increase sensitivity to heat by reducing the threshold of
heat receptor activation from 109 °F (43 °C) to 85 °F
(29 °C).The pain may be caused by overproduction of a protein
called CXCL5, which causes the activation of nerve fibres.
4.2 SUNBURNS GIVE OFF HEAT
Radiant energy can be viewed as photon
energy. The energy carried by each photon is
proportional to its frequency. When EM waves are absorbed by an object, the energy of the waves is converted
to heat. For example, sunlight warms
surfaces that it irradiates.
When our skin is exposed to sunlight,
we are also exposed to these photons which carry photon energy. Upon contact
with our skin, by abiding the Law of thermodynamics which states that the
energy cannot be destroyed but it can be changed, the photon energy changed
from radiant energy to heat.
The warmth of sunburn comes from increased
blood flow to the exposed part of the skin. Blood is rushing to the affected
area because of the inflammation to begin the process of repairing the damaged
cells by removal and replacement of damaged cells and that is where the sensation
of heat radiation comes from.
as moving light = radiation
Radiation is the heat transfer by electromagnetic waves or known as thermal
light waves. These waves are invisible to the naked eyes
Thermal radiation is a small part of the electromagnetic spectrum.
Infrared radiation is popularly known as “heat
radiation”, but light and electromagnetic waves of any frequency will heat
surfaces that absorb them.
Heat is energy in transit that flows due to
temperature difference. Unlike heat transmitted by thermal
conduction or thermal convection, thermal radiation can propagate
through a vacuum and space. Thermal radiation is characterized by a
particular spectrum of many wavelengths that is associated with emission from
an object, due to the vibration of its molecules at a given temperature.
5.0 VIEW OF THERMODYNAMICS ON HUMAN METABOLISM AND SUNBURN
Metabolism in humans is the
conversion of food into energy, which is then used by the body to perform
activities. It is an example of the first law of thermodynamics in action. Considering
the body as a system,we can use the first law to examine heat transfer, doing
work, and internal energy in activities ranging from sleep to heavy exercise.
For example, one major factor in such activities is body temperature,normally
kept constant by heat transfer to the surroundings, meaning that Q is negative
(i.e., our body loses heat). Another factor is that the body usually does work
on the outside world, meaning that W is positive. Thus, in such situations the
body loses internal energy, since ?U=Q?W is negative.
Take eating for example. The body
metabolizes all the food we consume. Eating increases the internal energy of
the body by adding chemical potential energy. In essence, metabolism uses an
oxidation process in which the chemical potential energy of food is released.
This implies that food input is in the form of work. Food energy is reported in
a special unit, known as the Calorie. This energy is measured by burning food
in a calorimeter, which is how the units are determined. Life is not always
this simple, as any dieter knows. The body stores fat or metabolizes it only if
energy intake changes for a period of several days. Once you have been on a
major diet, the next one is less successful because your body alters the way it
responds to low energy intake. Your basal metabolic rate is the rate at which
food is converted into heat transfer and work done while the body is at
complete rest. The body adjusts its basal metabolic rate to compensate
(partially) for over-eating or under-eating. The body will decrease the
metabolic rate rather than eliminate its own fat to replace lost food intake.
You will become more easily chilled and feel less energetic as a result of the
lower metabolic rate, and you will not lose weight as fast as before. Exercise
helps with weight loss because it produces both heat transfer from your body
and work, and raises your metabolic rate even when you are at rest.
Metabolic processes are chemical reactions and these
often involve generation of heat. Living organisms, however, do not follow all
the laws of thermodynamics. Organisms are open systems that exchange matter and
energy with their surroundings. This means that living systems are not in
equilibrium, but instead are dissipative systems that maintain their state of
high complexity. Cellular metabolism couples the spontaneous processes of
catabolism with the non-spontaneous processes of anabolism. In
thermodynamic terms, metabolism maintains the balance.
Entropy is associated with isolated systems, the
passage of time, uncertainty and disorder. In contrast, the experience with the
surrounding involves dissolving the barriers between the self and the
environment and is consistent with a state of minimum entropy that involves a
sense of order and certainty and the state of bliss. The idea that wellness and
positive psychological states require “open systems” is recognised within
common language with the idea of an “open heart” or “open mind”. Thus, while
the enlightened state suggests an open state of mind, the states of pain and
disease imply an increase in entropy within isolated systems created by a
disruption to the flow of matter, energy or information. Such disruption can be
seen to apply at many levels with disorder arising from different types of
obstructions, ranging from blocks in enzyme pathways and biochemical processes,
to mechanical disruptions in arteries, veins, ureters, intestines or nerves, as
well as blockages in emotional expression or thought processes creating a closed
heart or closed mind.
This analysis can be extended to the social and
cultural domains where interpersonal and cultural conflicts restrict
communication and result in social isolation, intolerance and violence. It is
ultimately information flow or communication that enables living systems at all
levels of organization to retain a high degree of order. Thus, in ordered
systems there is a transport of information from the environment to the most
highly ordered structures and therefore a dissipation of entropy from the most
highly ordered structures back to the environment. In this view, wellness
represents the drive towards maximal flow and minimal entropy production, which
then affords the greatest stability and resilience at any level of
Life is an organisational and
thermodynamic process that tends towards the maximum conversion of available
energy. The biochemical reactions produce or consume external metabolites, and
they connect internal metabolites, in constant concentrations in the cells at
their steady states. To do so, the cell must exchange energy and matter through
its membrane. The fundamental phenomena used by cells to reach their optimality
consist of a redistributing of the flow patterns through their metabolic
By using the bioengineering
thermodynamics, it has been highlighted how the different ions have different
effect on the use of energy by the cell to grow. To do so, a control of the
cells behaviours is introduced. Here, an electromagnetic field is used as a
control system, but other field could be used. Cells inside and outside an
electromagnetic field have been considered. The positive ions determines a
decreasing of the energy used by the cancer, such that the cancer cannot grow
as outside the field. On the other hand, the negative ion increase the use of
energy. It means that a control of ions can determine a control of the volume
growth of a cancer. This result can be extended to all the molecular fluxed
across the cell membrane, obtaining a possible bioengineering thermodynamic
approach to control the cancer growth.