Transcript 1.2a Chemistry of Life

Chemistry of Life
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Chemistry of Life
• Flowers emit a chemical perfume that
attracts butterflies, but the plant also
makes a noxious chemical in its leaves
which discourages the butterfly from laying
her eggs there.
• Insects interact via chemical messages
that range from “stay away” to “come mate
with me”.
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Rattlebox Moth
• Secrete a noxious chemical for defense,
particularly against spiders.
• This moth is a native of Central Florida.
• Its name comes from the rattlebox plant, the
source of the moth’s defensive chemical.
• This chemical also has an important role in its
mating strategy.
• While the moth was a caterpillar, it ate the
leaves from the rattlebox plant and stored this
chemical in its body.
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Rattlebox Moth
• While both male and female caterpillars contain
this chemical, the female moth receives an extra
dose at mating.
• During the eight hour copulation, the male
passes a large mass of sperm, nutrients, and
this chemical to the female, supplying additional
protection for her and for their offspring.
• Only a human bridegroom would buy life
insurance for his bride.
• This classy moth gives a gift she can really use-a life insurance policy that pays off every time
her life is in danger.
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•Nature’s Chemical Language
– The rattlebox moth
•
Produces chemicals important for mating and
defense
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Rattlebox Moth
• During the courtship dance, the male moth release is
into the air puffs of this chemical; the female, sensing it,
can assess how much of this chemical he has.
• There are some kinds of chemical signaling in humans
as well. For instance, chemicals in the armpit of a male
can apparently regularize a female companion’s
ovulatory cycle.
• Chemicals play many more roles in life than signaling.
Chemicals make up our bodies as well as the bodies of
other organisms, and they also make up the physical
environment. To understand biology, we should first
look at where it all begins: chemistry.
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An element is an atom with a certain number of electrons
(electrical charges) circling around it in an orbit.
Outermost electron shell (can hold 8 electrons)
First electron shell (can hold 2 electrons)
Electron
Hydrogen (H)
Atomic number = 1
Carbon (C)
Atomic number = 6
Nitrogen (N)
Atomic number = 7
Oxygen (O)
Atomic number = 8
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ELEMENTS
• 96% of the human body is composed of just four
elements.
– Carbon (C)
– Hydrogen (H)
– Oxygen (O)
– Nitrogen (N)
• The other 4% of elements in our body
– Calcium, phosphorus, potassium, sulfur, sodium,
chlorine, and magnesium.
– These elements are involved in important functions
such as bone formation, nerve signaling, and DNA
synthesis.
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Trace Elements
• Iron
– Needed by all forms of life for transporting the
oxygen in the blood.
• Iodine
– only required by certain species; it is an
ingredient of a hormone produced by the thyroid
gland. Iodine is commonly added to table salt to
prevent the formation of goiters.
• Fluorine
– added to water in some communities to reduce
tooth decay
• Zinc
• Manganese
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Goiter
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Vitamin-Fortified Foods
• Chemicals are added to food to help preserve it, make it
more nutritious, or simply to make it look better.
• Iron, for example, is a trace element that is commonly
added to foods.
• You can actually see the iron that has been added to a
fortified cereal by crushing the cereal and then stirring a
magnet through it.
• Vitamins are also frequently added to cereal.
• A vitamin consists of more than one element and is an
example of a compound, which we will consider next:
Elements combine to larger units called compounds.
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Trace elements
are essential to
human health and
may be added to
food or water
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Compounds
• Two or more elements
• Compounds are much more common than pure
elements.
• In fact, few elements exist in a pure state in nature.
Many compounds consist of only two elements; for
instance table salt (sodium chloride) has equal parts of
the elements sodium and chlorine.
• Pure sodium is a metal and pure chlorine is a poisonous
gas. Chemically combined, however, they form a
common seasoning.
• This example shows the emergence of novel properties
with a higher level of structural organization. We will see
this in biology too, as we study the adaptations of
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organisms as they evolved.
Elements can combine to form compounds
Sodium
Chlorine
Sodium Chloride
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Compounds
• Hydrogen (H) and Oxygen (O) = H2O
• Sodium (Na) and Chlorine (Cl) = NaCl
• Demonstrates new properties with a
higher level of structural organization
• Carbon, hydrogen, oxygen, and nitrogen
form most of the compounds in living
organisms
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– Sodium and chloride ions
•
Bond to form sodium chloride, common table salt
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Compounds
• Most of the compounds in living organisms contain at least
three or four different elements, mainly carbon, hydrogen, oxygen,
and nitrogen.
• Vitamin K, for example, is formed of just carbon, hydrogen, and
oxygen.
• Proteins are compounds containing carbon, hydrogen, oxygen,
nitrogen, and a small amount of sulfur.
• Different arrangements of the elements determine unique properties
for each compound.
• There are two groups of compounds in our bodies; organic and
inorganic.
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INORGANIC COMPOUNDS
• Contain NO carbon atoms
• SALTS
– Found in body fluids and is needed for
muscle contraction and nerve conduction.
• WATER
– The body is 70% water.
– It keeps the body from overheating
– It also prevents drastic changes in
temperature.
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Water
• If you have ever burned your finger on a metal pot while
waiting for the water in it to boil, you know that water
heats up much more slowly than metal.
• Water has a better ability to resist temperature change
than most other substances.
• Earth's giant water supply moderates temperatures,
keeping them within limits that permit life.
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Water
• A large body of water can store a huge amount of heat
from the sun during warm periods.
• At cooler times, heat given off from the gradually cooling
water can warm the air.
• That's why coastal areas generally have milder climates
than inland regions.
• Water's resistance to temperature change also stabilizes
ocean temperatures, creating a favorable environment
for marine life.
• And at 70% of your body weight, water helps moderate
your internal temperature.
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Water
• Liquids vaporize into a gas when some of their
molecules move fast enough.
• When heat is applied to a liquid, it makes the molecules
move faster and bump into each other, causing the
hydrogen bonds break, allowing vaporization to occur.
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Water Molecule
(–)
(–)
O
H
(+)
H
(+)
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Water molecules form weak bonds between
each other called hydrogen bonds
(–)
Hydrogen bond
(+)
H
O
(+)
(–)
H
(–)
(+)
(–)
(+)
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Ice is less dense than liquid water
– Hydrogen bonds hold molecules in ice farther
apart than in liquid water
Hydrogen bond
Ice
Hydrogen bonds are stable
Liquid water
Hydrogen bonds
constantly break and re-form
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– Insects can walk on water due to surface
tension
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Water
• Another way water moderates temperatures is by
evaporative cooling.
• When a substance evaporates, the surface of the liquid
remaining behind cools down as the hottest molecules
leave.
• Evaporative cooling helps prevent land-dwelling
organisms from overheating.
• Evaporation from a plant’s leaves keeps them from
becoming too warm in the sun, just as sweating helps to
dissipate our excess body heat.
• On a much larger scale, the evaporation of surface
waters cools tropical seas.
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How do land organisms
keep from overheating?
• Evaporative cooling
– Plant’s leaves
– Human sweating
– Evaporation of surface
waters cools tropical
seas.
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Water is the solvent of life
• Solution: a liquid consisting of a uniform
mixture of two or more substances.
• Solvent: the dissolving agent
• Solute: the substance that is dissolved
• Water is the solvent inside all cells, in
blood, and in plants, and it dissolves an
enormous variety of solutes necessary for
life.
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The chemistry of life
• The chemistry of life is sensitive to
acidic and basic conditions
• In water solutions, a very small percentage
of the water molecules actually break
apart into ions.
• The ions formed are called hydrogen ions
(H+) and hydroxide ions (OH-).
• The proper balance of these ions is very
critical for the proper functioning of an
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organism.
Acids and Bases
• Some water molecules break apart into ions.
– Hydrogen ions (H+)
– Hydroxide ions (OH-)
• Acid: excess hydrogen ions (H+)
– hydrochloric acid in your stomach
• Base: excess hydroxide ions (OH-)
– Ammonia is a base
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Acids and Bases
• We use the pH scale to describe how acidic or
basic a solution is.
• The scale ranges from 0 (most acidic) to 14
(most basic).
• Pure water and other solutions that are neither
acidic nor basic are said to be neutral; they have
a pH of 7.
• The pH of the solution inside most living cells is
close to 7.
• Even a slight change in pH can be harmful.
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pH scale
H+ H+
Acidic solution
OH–
OH–
OH–
H+ H+ –
OH– OH
H+ H+ H+
Neutral solution
OH–
OH–
OH– H+ OH–
OH– OH– –
OH
H+
Basic solution
NEUTRAL
[H+]=[OH–]
Increasingly BASIC
(Lower concentration of H+)
• Neutral: pH = 7
• Acid: pH < 7
• Base: pH > 7
+
H+ H
H+ OH– H+
OH– H+ H+
Increasingly ACIDIC
(Higher concentration of H+)
pH scale
0
1
2
Lemon juice, gastric juice
3
Grapefruit juice, soft drink
4
Tomato juice
5
6
Human urine
7
Pure water
Human blood
8
Seawater
9
10
Milk of magnesia
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Household ammonia
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Household bleach
13
Oven cleaner
14
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Acid Rain
• Imagine arriving for a long awaited
vacation at a mountain lake only to
discover that since your last visit a few
years ago, all fish and other forms of life in
the lake have perished because of
increased acidity of the water.
• Over the past quarter-century, thousands
of lakes in North America, Europe, and
Asia have suffered that fate. This problem
is due to acid rain.
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Acid Rain
• Acid rain = pH well below 7
• Results from sulfur and nitrogen in the
air.
• These elements react with water vapor in
the air to form sulfuric acid and nitric acid,
which fall to the earth in rain or snow.
• Acid rain with a pH of 1.7 (almost as acetic
as the digestive juices in the human
stomach) has been recorded in Los
Angeles.
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Acid Rain
• Sulfur and nitrogen in the air comes from
the burning of fossil fuels such as coal, oil,
and gas.
• Electrical power plants that burn coal
produce more of these pollutants than any
other single source.
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Sulfur and nitrogen in the air comes
from the burning of fossil fuels
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The Effect of Acid Rain
• Lakes:
– most pronounced in the spring
– Kills eggs and young fish
• Forests:
– Ions bind with essential minerals needed
for plant growth
– Leaves behind toxic levels of aluminum
• Cities:
– corrosion of buildings and statues
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Acid Rain in Lakes
• The surface snow melts first, drains down,
and sends much of the acid that has
accumulated over the winter into lakes and
streams all at once.
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Lakes
Most
pronounced in
the spring
Kills eggs and
young fish
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Acid Rain in Forests
• Acid rain has also taken a toll on forests. When acid
precipitation falls on land, it washes away mineral ions,
such as calcium and magnesium, which are essential
nutrients for plant growth.
• At the same time, minerals such as aluminum reach
toxic concentrations.
• In cities, acid precipitation causes a great deal of
corrosion of buildings and statues.
• That is why laws were enacted that require reductions in
emissions to help alleviate the problem.
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Forests
Ions bind with
essential
minerals
needed for plant
growth
Leaves behind
toxic levels of
aluminum
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Corrosion of
buildings and
statues
Cities
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Chemistry of Life
• Every organism has a delicate biochemistry that needs
to be maintained.
• One spring, a baby finch collapsed with exhaustion on
my patio.
• Since it was exhausted, it probably wasn’t good at
finding food and water yet.
• That means it was dehydrated and hungry.
• I knew to get an eyedropper and give it water with sugar
in it because those are the two main things it needs right
away.
• We discussed water, now let’s get to sugars.
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ORGANIC COMPOUNDS
• Always contain carbon
– Carbohydrates
– Lipids
– Proteins
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CARBOHYDRATES
• Store energy for a
short time
– Simple (sugars)
– Complex (starches)
• Cellulose (fiber) is in
plants only
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SIMPLE CARBOHYDRATES
• Known as sugars
• Quick source of
energy
• Burned off fast
–
–
–
–
Glucose
Sucrose
Fructose
Lactose (some people
are lactose intolerant)
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Lactose Intolerance
• Got milk? Most of the world's people cannot easily
digest milk-based foods.
• Milk and other dairy products have long been recognized
as highly nutritious foods, rich and proteins and minerals
necessary for good teeth and strong bones.
• But for millions of people, those health benefits come
with digestive discomfort.
• Such people suffer from lactose intolerance, or the
inability to properly break down lactose, the main sugar
found in milk.
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Lactose intolerance
is common world-wide
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Lactose Intolerance
• For those with lactose intolerance, the problem starts
once lactose passes through the stomach and enters the
small intestine.
• To absorb this sugar, digestive cells need to secrete an
enzyme called lactase, which is necessary to break
down lactose.
• An enzyme is a protein that breaks down larger
molecules into smaller ones.
• Those with lactose intolerance produce insufficient
amounts of the enzyme and the lactose cannot be
properly digested.
• This leads to symptoms of nausea, cramps, diarrhea,
and gas.
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• .
Lactose Intolerance
• At birth, nearly everyone produces enough lactase
• Therefore, milk provides excellent nourishment for
infants.
• But after the age of two, lactase levels start to decline in
most of the world’s populations. In the United States,
75% of African Americans and Native Americans and
90% of Asian-Americans are lactase deficient once they
reach their teenage years.
• People of European descent are the only group that
does not suffer much from lactose intolerance.
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Lactose
• Present in bottled
salad dressings,
lunchmeat,
prescription drugs.
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Lactose
• Currently, lactose intolerance cannot
be corrected by gene therapy to treat
the underlying cause
• The symptoms of lactose intolerance can
be controlled through diet.
– In many Asian cultures, beverages are made
from soy or rice instead of milk.
– Milk-based foods pre-treated with lactase.
– Lactase in pill form can be taken with food
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Lactose
• Lactose intolerance, with its interplay between genes
and milk sugar, illustrates the importance of biological
molecules to the functioning of living cells and to human
health.
• In people who easily digest milk, lactose (a sugar), is
broken down by lactase (a protein), which is produced by
a gene made of DNA (a nucleic acid).
• If the gene for lactase production is not active, lactase is
not present.
• And the presence of lactase can mean the difference
between delight and discomfort when someone
contemplates an ice cream sundae.
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“Sweet” Taste Receptors
• The taste we describe as sweet has been a beloved sensation
throughout human history.
• However, sugars are not the only substances perceived as sweet;
there are other chemicals that can trigger the same sensation.
• We perceive sweetness when molecules of a substance attach to
the “sweet” taste receptors on our tongue, triggering a message to
the brain.
• Many different kinds of molecules can bind to our “sweet” taste
receptors, each causing a similar message to be sent.
• The glucose and fructose in honey taste sweet but so does the
laboratory-produced compound called aspartamine (Equal and
NutraSweet).
• Compared to table sugar (sucrose), fruit sugar (fructose) is four
times sweeter.
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“Sweet” Taste Receptors
• We perceive sweetness when molecules of a
substance attach to the “sweet” taste receptors
on our tongue.
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“Sweet” Taste Receptors
• Aspartamine (Equal and NutraSweet)
• Compounds that bind more tightly to
“sweet” taste receptors send stronger
“sweet” messages to the brain.
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“Sweet” Taste Receptors
• The chemical shape of a compound determines how well it fits into a
taste receptor.
• Compounds that bind more tightly to “sweet” taste receptors send
stronger “sweet” messages to the brain.
• Some artificial sweeteners are much sweeter than sucrose because
their molecules fit more snugly into our sweet taste receptors than
natural sugars.
• Neotame, a new artificial sweetener that received FDA approval in
2002, has been rated 8000 times sweeter than sucrose. Therefore,
smaller quantities are needed.
• However, some sugar substitutes also bind to other kinds of taste
receptors on the tongue. For example, a sweetener may have a
bitter aftertaste because it also binds to “bitter” receptors.
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STARCH
• The storage form of
glucose in plants
• When we eat breads, corn,
rice, potatoes, and cakes,
we convert it to glucose.
• These don’t break down to
glucose as easily, so they
tend to get stored and are
only broken down when
there is not enough glucose
available.
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CELLULOSE
• Only found in plant cell
walls
• Our body is unable to
break it down, so it
passes through our
digestive tract.
• That is what is referred
to as eating fiber.
• The fiber portion of is the
wall of each plant cell.
Eating fiber helps a person who has
constipation. Foods that are high in fiber are
most likely derived from plants.
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Fiber
• Fresh fruits, vegetables, and grains are rich in fiber.
• The fiber portion of each of these foods is the wall of each cell.
• The contents of each cell contain the carbohydrates which can be
digested.
• This is one reason you should chew your food well; crushing up the
cell walls will release the nutrients.
• If you swallow a whole kernel of corn, it will pass right through your
digestive tract without being digested.
• You may have heard the term cellulite referring to fat. However,
there is no such thing; it is just regular fat, which we’ll talk about
now. Some companies made up the term and said their cream can
dissolve it: Wrong!
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LIPIDS
• Lipids don’t
dissolve in water.
– FATS AND OILS
• Fats are animal lipids
• Oils are plant lipids
– STEROIDS
When we ingest
(eat) oils, we
convert them to fats.
One gram of fat
stores more than
twice as much
energy as one gram
of starch.
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FATS
• Long-term energy storage
• Insulate against heat loss
• Forms protective cushions around organs
1) SATURATED FATTY ACIDS are solid at
room temperature, like butter and lard
(animal fats).
2) UNSATURATED FATTY ACIDS are
liquid at room temperature, such as
vegetable oils (plant fats)
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Fats
• Most plant fats are unsaturated oils,
whereas most animal fats are saturated
solids.
• Diets rich in saturated fats contribute to
cardiovascular disease by promoting a
condition called atherosclerosis.
• In this condition, the lipids deposits called
plaques build up within the walls of blood
vessels, reducing blood flow.
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Atherosclerosis
• Caused by
diets rich in
saturated fats
• The lipids
deposits
(plaques) build
up within the
walls of blood
vessels,
reducing blood
flow.
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STEROIDS
• Formed from
cholesterol
• Cholesterol is found
in the cell membranes
of our body.
• Examples of steroids
that our body makes
are estrogen and
testosterone.
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Anabolic Steroids
• Synthetic form of the male hormone
testosterone
• Testosterone causes a buildup
(anabolism) in muscle and bone mass in
males during puberty and maintains
masculine traits throughout life.
• Because anabolic steroids structurally
resemble testosterone, they also mimic
some of its effects.
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Anabolic Steroids
• As a prescription, steroids are used to treat anemia and
diseases that destroy body muscle.
• Overdosing may cause violent moods swings (“steroid
rage”) and deep depression.
• The liver may be damaged, leading to cancer.
• High blood pressure
• The body reduces its output of natural male sex
hormones
– Men: shrunken testicles, reduced sex drive, infertility, and breast
enlargement.
– Women: menstrual cycle disruption and development of
masculine characteristics, including facial hair.
– Teenagers: bones may stop growing, stunting growth.
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Steroid Abuse
• Despite risks associated with steroid use, some athletes
use steroids to gain a competitive edge.
• Sports organizations banned their use, implement drug
testing, and penalize violators.
• In 2003, the discovery of a new designer steroid rocked
the sports world.
• THG is a drug modified to avoid detection in ordinary
drug testing.
• The drug was discovered when a track coach mailed a
syringe containing a sample of it to the US Anti-Doping
Agency.
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Steroid Abuse
• With that sample, the agency was able to develop a test
that revealed the substance’s use among track and field
athletes and professional football players, so the
International Olympic Committee has begun retesting
frozen urine samples from the 2002 Winter Games.
• The US FDA declared THG an illegal steroid.
• In 2004, a British sprinter became the first athlete to be
penalized for its use, with a permanent exclusion from
the Olympics following his positive test for THG.
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Olympic Drug Testing
• THG was a new steroid
that was not detectable in
ordinary drug testing
before 2003.
• Performance-enhancing
drugs bar an athlete from
getting a medal.
• Blood doping: blood is
removed from an
athlete's body several
weeks before a
competition and then reinjected into the body
right before the event.
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Performance-Enhancing Drugs
• Discussion
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PROTEINS
• PROTEINS are compounds that make up most
of our body.
• Our hair, nails, tissues, ligaments, cartilage,
bone, tendons, muscles, and organs are
made of proteins.
• Other proteins we have are enzymes, which
function to speed up metabolic reactions and
break down larger compounds into smaller
ones.
• A protein is made from a string of amino acids.
Each of our many thousands of different kinds of
proteins has a unique shape that corresponds to
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a specific function.
PROTEINS
• Other types of proteins include the anti-bodies of our
immune system, hormones that coordinate bodily
activities, hemoglobin in red blood cells which deliver
oxygen to working muscles, transport proteins that move
sugar molecules into cells for energy, storage proteins,
the protein of egg white, and milk proteins which provide
amino acids for baby mammals.
• Plants also have storage proteins for the developing
embryos in their seeds.
• Since proteins are made of amino acids, in order to
understand what a protein is, we have to talk about
amino acids (AA’s).
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AMINO ACIDS
• The building blocks of protein
• They are tiny compounds, made of just a carbon atom
and a few other atoms.
• Although there are many thousands of different types of
proteins, they are all made up of a various combination
of only 23 amino acids.
• They are like beads on a necklace. How they are
arranged on the string determines the type of necklace.
Each bead is an amino acid, and the whole necklace is
the protein.
• A protein’s specific shape determines its function. A
bunch of the same types of necklaces (proteins) woven
together makes up our tissues.
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PROTEINS
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Denatured Proteins
• If a protein becomes denatured, the amino acid chain
unravels, causing a loss in shape and, as a result,
function.
• Things that can denature a protein include salt
concentration, pH, and excessive heat.
• You can see an example of protein becoming denatured
by frying an egg. Heat quickly denatures the clear
protein surrounding the yoke, making them solid, white,
and opaque.
• One of the reasons why extremely high fevers are so
dangerous is that some proteins in the body become
denatured and cannot function.
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Denatured Proteins
• Denatured proteins are
those whose amino acid
chains becomes unraveled,
and results in loss of
function.
• Proteins are denatured by
– salt concentration
– pH
– excessive heat
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NUCLEIC ACIDS
• Special type of amino acids that make
up DNA and RNA
• DNA makes up our genes
• Genes
– store information about how to replicate,
including how to arrange the amino acids
in the new cell to form the proper proteins
for the body.
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TYPES OF NUCLEIC ACIDS
• DNA
– The genetic material that organisms inherit
from their parents consists of DNA.
– Genes are the specific stretch of a DNA
molecule that programs the amino acid
sequences.
• RNA
– Messenger molecules that take a copy of the
DNA blueprint out of the nucleus and into the
cell where it is used to make proteins
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NUCLEOTIDES
Nucleic
acids are
made of
nucleotides
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DNA and RNA
• An architect who spends a lot of time designing an
original blueprint for a building does not take this
precious document down to the dusty construction site.
• Instead, he makes a copy and leaves the original at
home in a safe place.
• Likewise, DNA in the nucleus does not put its genetic
information to work directly by leaving the nucleus.
• It works through an intermediary called RNA, which can
enter the nucleus from the cytoplasm, make a copy of
the gene and take it outside of the nucleus into the
cytoplasm, were the protein is actually built.
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DNA and RNA
• To do this, the information in DNA is first copied onto a
strand of messenger RNA (mRNA), which is like
stamping an impression in clay.
• Since the clay impression is not an exact copy of the
original, but is instead a reverse copy, the DNA then
needs to be translated before the protein is built.
• This is done by transcription RNA (tRNA).
• After the protein is built in the cytoplasm, it is either used
by that cell or transported outside of the cell so it can be
taken wherever else in the organism it is needed.
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NUCLEOTIDES
• Nucleic acids are made out of a string of
nucleotides
• There are only four types:
– adenine (A)
– thymine (T)
– cytosine (C)
– guanine (G)
A sample protein sequence: AATCAGCT
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NUCLEOTIDES
• A sample protein sequence: AATCAGC T
A
• If you were to remove the last letter in that sequence, a
completely different protein would form.
• Likewise, if you were to substitute the last letter in that
sequence for a different letter, you would also get a
completely different protein.
• And of course, if you insert additional letters, you would
have a new protein.
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NUCLEOTIDES
• Actually, a DNA “string of beads” is actually doublestranded.
• Each of the nucleotides (A,T,C,G) on one strand fits like
a puzzle piece into the nucleotides on the other strand.
• The nucleotide adenine (A) always pairs up with thymine
(T), and cytosine (C) always pairs up with guanine
(G)…these are called base pairs.
• Therefore the two strands of DNA lock together like a
jigsaw puzzle.
• The two strands of this DNA “string of beads” are also
twisted like a coiled telephone cord. This structure is
called a double helix.
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NUCLEOTIDES
• Each of the nucleotides
(A,T,C,G) on one strand
fits like a puzzle piece
into the nucleotides on
the other strand.
• adenine (A) pairs up
with thymine (T)
• cytosine (C) pairs up
with guanine (G)
• These are called base
pairs.
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DNA
• The two strands of
this DNA are also
twisted into a double
helix
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DNA
• Most DNA molecules are very long, with
thousands or even millions of base pairs.
• One long DNA molecule may contain
many genes, each one being a specific
series of hundreds or thousands of
nucleotides.
• The specific sequence of nucleotides in a
gene is the information that programs the
primary structure of a protein.
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ATP
• The type of protein that provides all the energy
to cells.
• When food is broken down to glucose for
energy, ATP is what is released, which is the
actual energy molecule.
• The more ATP that is produced, the more
energy we have.
• When we inhale oxygen, it is used in a process
called respiration, which produces ATP for
energy. That is why we breathe.
• Just remember that ATP is an energy
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molecule.
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