Lesson 3.1 Introduction to Energy

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Transcript Lesson 3.1 Introduction to Energy

What can the human body withstand?
Mauro Prosperi
The Story of Mauro Prosperi, a 39 year old
Italian policeman took part in the 1994
Marathon des Sables (Marathon of the Sands)
in Morocco.
A Major Sandstorm
Partway through the six day, 145 mile (233 km) event, a
sandstorm caused him to lose his way.
He ended up disoriented, after which he ran and walked about
three hundred kilometres in the wrong direction.
Mauro had a compass but no reference points and it took a
while before he realized that he had strayed off the route.
"I wasn’t panicked, I just despaired. Fear, the type that doesn’t
paralyze you is important. It forces you to think and
"I stopped and turned my back to the wind, then covered my
face with a special sandstorm scarf and glasses. I eventually
found a log to block the wind, but I needed to keep moving a
bit to keep from getting buried. The storm lasted eight hours,
and when the winds died down, I didn’t know I was lost".
Shifting Into Survival Mode
Mauro shifted immediately into survival mode and the first
thing he did was to urinate into a water bottle.
He knew that this first urination was going to be the
clearest and most drinkable in the event that he didn’t
come across a fresh water supply.
Mauro knew enough about desert survival to only walk in
the morning and evening, and to relax in the shade during
the midday heat.
After three days of wandering, taking sips of that initial
urine, he was enveloped by another sandstorm that lasted
for twelve hours.
Drinking Bat’s Blood
He found a small Muslim shrine, hung his Italian flag out
front and crawled inside, where he finally found some
He caught two small bats, twisted off their necks and
drank their blood.
* Cooking first, and then eating the bats would have just
accelerated the dehydration.
And Then An Attempted Suicide!
"I reasoned that if I died in that shrine, by body would
eventually be found. If I died while walking, my body
would never be found. I wanted my family to be able to
recover my body so they could come to terms with my
He wrote a note to his wife with a piece of charcoal and
then slit his wrists and waited to die, but his blood had
thickened and wouldn’t drain.
But Mauro took that as a sign!
Renewed Determination And Finding An Oasis
"It gave me more confidence. I started to view the desert as a
place where people can live. I started to think of myself as a
man of the desert. I wanted to see my family and friends again
and I concentrated on that".
He decided again to try and walk his way to safety and headed
for a mountain range in the distance.
Five days after leaving the shrine, and eight days drinking
almost nothing but urine, he found a small oasis.
Mauro resisted the temptation to drink his fill of water which
would have caused severe cramping, and instead took a
reasonable, calculated amount.
Taken To Safety By Nomads
Two later days he encountered some Tuareg nomads,
who took him on camel-back to a nearby Algerian
military camp and from there to a hospital.
He was around 186 (300 km) miles off route, and
reportedly had lost between 30 and 40 pounds (18 kg)
in body weight.
1.Digestive system-no food/water
2.Integumentary system-Sweating, sun burn
3.Cardiovascular system-little bit of everything
4.Nervous system-Mirages
5.Respiratory system- Sand in lungs, heat
6.Endocrine system7. Urinary system-drink urine
8. Muscle System-
Essential Question:
1. What are the resources the human
body needs to survive?
 Oxygen
 Water
 Food
• Pair up with a partner to complete your
Powering The Human Body Chart
Create This Chart in Your Lab Journal
Resource #1
Body Systems
Resource #2
Resource #3
Essential Question:
2. What role does food play in the
human body?
Food serves as a source of energy for
the body as well as a source of fat and
insulation. This fat cushions organs and
protects the human body.
Food includes macromolecules (Lipids,
Carbohydrates & Proteins), as well as vitamins
& minerals
Quick energy source
Long term energy source,
cushioning of organs,makes
up much of brain
 Proteins
Build & repair body tissues
Most doctors agree that healthy humans can go up to
eight weeks without food as long as they have water.
Being strong and in good physical shape can help you
survive longer, but so does having extra body fat.
Body stores energy needed to live in the form of fat,
carbohydrates and proteins.
Carbs are the first thing to be used up
Then proteins. If you get to the point that your body is
using up proteins, basically the body itself, then you're in
bad shape.
Fat goes next, which explains why people with more of it
can survive longer.
*Essential Question:
*3. What role does water play in the human
1. Dissolves other materials & allows
them to flow (in blood)
2. Gives cells structure (just right
amount needed to prevent shrinking
and exploding)
3. Allows food to digest & pass
through intestinal walls into
4. Carries waste products out of body
(in urine)
5. Helps send electrical messages
6. Regulates homeostasis of body
temperature (evaporation/sweating)
7. Lubricates structures (i.e. allows
fecal matter to pass through large
8. Protective barrier around organs
In hot conditions with no water, dehydration can set in within an
A baby locked in a hot car or someone who is physically overexerted
in the heat without replacing fluids can actually die in a period of
several hours.
We lose water through sweat, urine, feces and even breathing.
This water needs to be replaced in order for our organs to continue
to work properly.
In severe heat, an adult can lose as much as 1.5 liters of water
through sweat alone.
The main risk without water in high heat is that your body
temperature will continue to rise and you'll suffer from heat stroke.
Drinking water will cool you down and lower your core
Essential Question:
4. What role does oxygen play in the
human body?
Oxygen is required to feed the body’s
tissues and produce ATP in aerobic
cellular respiration. The physical act of
breathing assists with gas exchange and
the removal of harmful gases from the
Of all the chemical elements, oxygen is the
most vital to the human body.
We would survive for only minutes without
Oxygen is the life-giving, life-sustaining
element. Approximately 90% of the body's energy
is created by oxygen.
Nearly all of the body's activities, from brain
function to elimination, are regulated by oxygen.
The ability to think, feel and act is derived from
the energy supplied by oxygen.
Essential Question:
5. What human body systems work to
create, process or distribute the
body’s main power sources?
 The Rule of Threes states that the
human body can survive for:
3 minutes without oxygen
3 days without water
3 weeks without food
 However... other factors can prolong
or shorten these times.
 Complete Activity 3.1.2 and fill in the rest
of their chart
How do personal factors and
environmental factors impact the body’s
ability to survive without air, food or water?
With a group of 4 complete your
You have 20 minutes to complete
Factors that can
* children and
Mammalian Response
* Temperature- colder
is better
* Altitude- lower is
Factors that can
* Lack of oxygen
transfer as age
increases due to
environmental and
lifestyle choices.
* Temperature- warmer
is worse
* Altitude- less oxygen
at higher altitudes
Factors that can
*Activity Level
* Lower activity level
uses less water
* Temperature- colder
is better
*Food intake
* Some foods contain
higher amounts of
Factors that can
*Activity Level
* Increased activity leads to
higher level of cellular
respiration resulting in
increased water loss. as
well as perspiration.
* Temperature- warmer is
worse = increased
*Age and Gender
* Women have less water
* Children have a greater
surface area to volume
Factors that can prolong.
*Initial body state
* people with a higher BMI
have more stored energy
Factors that can shorten.
*Initial body state
* people with a lower BMI
have less stored energy
*Metabolic rate
*Metabolic rate
* Adults lower
* Women lower
* Differences among
* Temperature-Average
temperatures better.
* Children higher
* Men higher
* Differences among
* Extremes are worse.
How can a person prepare their bodies
for a fuel (food) shortage?
*Nucleic Acids
Homeostasis The maintenance of relatively stable
internal physiological conditions (as body
temperature or the pH of blood) in higher
animals under fluctuating environmental
Macromolecule A very large molecule (as of a protein,
nucleic acid, or carbohydrate) built up
from smaller chemical structures.
A natural feature or phenomenon that
enhances the quality of human life.
What helps food
Enzymes which
act as a catalyst
What is a catalyst?
• Catalysts help a reaction happen
faster but do not change
themselves during the reaction.
• A catalyst lowers the amount of
energy needed so that a reaction
can happen more easily. A catalyst
is all about energy.
1. Add 10 mL of hydrogen peroxide to a
graduated cylinder. Add 1 drop of detergent
solution. Swirl gently and watch the solution
for any bubbling.
2. Use the end of a popsicle stick to add a
small amount of yeast to the hydrogen
peroxide in the graduated cylinder and
3. Place the graduated cylinder on the table
and watch for any bubbling.
4. Hold the graduated cylinder to see if there
seems to be any change in temperature.
• Pair up with a partner
• Complete parts A,B and C
• Share with class your
*Structurally- enzymes are proteins and
have a complex, 3-dimensional shape
*Functionally- they act as biological
catalysts; there are different models
concerning function (Lock & Key Model and
Induced Fit Model)
*Action- enzymes work by lowering the
activation energy of chemical reactions;
they are very specific, with each enzyme
working on a particular substance, the
Coenzyme: A substance that enhances the
action of an enzyme.
Coenzymes are small molecules. They cannot
by themselves catalyze a reaction but they
can help enzymes to do so.
Coenzymes are organic nonprotein molecules
that bind with the protein molecule
(apoenzyme) to form the active enzyme
1) Lock-and-Key Model - A model for
enzyme-substrate interaction
suggesting that the enzyme and the
substrate possess specific
complementary geometric shapes
that fit exactly into one another.
Like a key into a lock, only the
correct size and shape of the
substrate (the key) would fit into
the active site (the key hole) of the
enzyme (the lock).
2) Induced-fit model- A model for
enzyme-substrate interaction to
describe that only the proper
substrate is capable of inducing the
proper alignment of the active site
that will enable the enzyme to
perform its catalytic function. It
suggests that the active site
continues to change until the
substrate is completely bound to it,
at which point the final shape and
charge is determined.