The Chemistry of Life
• The FIVE primary elements of Life and
all Living things(You must know these symbols and the
corresponding names)
• C carbon
• H hydrogen
• O oxygen
• N nitrogen
• P phosphorus
• When elements are combined to
make molecules and compounds, the
subscript number represents how
many atoms of each element is in
the molecule.
• For example, water H2O is really 2
hydrogen and 1 oxygen atoms.
• are those that contain both carbon
(C) and hydrogen (H) and usually
other atoms.
C6H12O6 and
methane, CH4.
Like glucose,
•We
are investigating organic
Macromolecules- BIG compounds
• are those that DO NOT contain
both carbon (C) and hydrogen
(H).
Like water
H2O and carbon
dioxide CO2 .
• O2 OXYGEN
• CO2 CARBON DIOXIDE
• H2O WATER
Processes we have seen these in:
• photosynthesis
• Cellular respiration
• Carbon, water, & oxygen cycles
• Greenhouse gases (CO2 & H2O)
O2
C6H12O6
CO2
C8H18
• Water covers most of the planet (74%
fresh and salt) and makes up the
greatest percentage of ALL living
organisms.
• Depending on temperature and
volume, humans can live WITHOUT
WATER for only one to ten days
H2 O
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An important property of the water molecule
is that it is POLARMeaning it has an uneven distribution of
charges, a slightly positive end and a slightly
negative end.
NONPOLAR molecules have an
even distribution of charges
like petroleum
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The slightly positive and negative ends of the
water molecule allow it to act like a magnet
(having positive and negative ends or poles),
so that it can interact with and dissolve many
other polar substances. As consequence,
water is known as the universal solvent.
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are formed between polar molecules
involving slightly positive Hydrogen and
slightly negative Oxygen or Nitrogen atoms.
Hydrogen bonds DO NOT change the
molecules involved, these bonds are weak
and temporary yet are essential in ALL living
organisms.
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Adhesion-is the property where different
molecules are attracted to each other.
Look at the drop of water hanging off of the leaf
in the picture…do you think that water has
adhesive properties?
Explain?
Looking at the pictures of
water on a penny, can you tell
if water is adhering to the
penny?
What would adding soap to
the number of drops you fit on
the penny?
Soap decreases the ability of
water to form Hydrogen bonds.
Cohesion-is the property
where the same type of
molecules are attracted to each
other.
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Try it!
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Place a couple drops of water on the piece of
wax paper (very hydrophobic)
Push the drops around and see what happens
when they come together
Why does this occur?
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Surface tension is cohesion at the surface of a
liquid due to hydrogen bonds between molecules
at the surface. This forms a strong surface "film”.
This is why some animals
can “walk on water” and
why very heavy boats float!
Capillary Action is where
the properties of water,
adhesion and cohesion,
work to draw liquids
against gravity.
Plants depend this property
of water to get water from
their roots to their leaves.
Water is called the universal solvent because of
all the properties it has…polarity, cohesion, and
adhesion and its ability to form hydrogen bonds.
A solution is a uniform mixture of at least two
substances, like salt and water salt water
-SOLVENT = water (does the dissolving)
-SOLUTE = salt (is what is being dissolved)
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Like dissolves like means that the chemical
properties are similar enough that if placed
together they would uniformly mix, making a
solution.
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Oil and water do not mix (for long)
because one is very polar and
the other is very nonpolar.
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Because water is so important there are
two more important watery terms you
need to knowHydrophilic –water loving molecules, will
easily dissolve in water
Hydrophobic -water fearing molecules,
do not mix/dissolve in water and often
move AWAY from water
C, carbon, H, hydrogen, O, oxygen, N,
nitrogen, and P, phosphorus
 ALL organic compounds MUST contain
both carbon and hydrogen
 Glucose, C6H12O6 and methane CH4
two common organic molecules
 Macro=BIG
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A
monomer is a simple compound
that can join together to for polymers
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A polymer is a large molecule
(macromolecule) composed of
repeating structural units connected
by covalent chemical bonds
• O2 OXYGEN
• CO2 CARBON DIOXIDE
• H2O WATER
Processes we have seen these in:
• photosynthesis
• Cellular respiration
• Carbon, water, & oxygen cycles
• Greenhouse gases (CO2 & H2O)
Remember Macro mean BIG,
sooooo…these are mostly very big
molecules, they are as follows:
1. Carbohydrates
2. Lipids
3. Nucleic Acids
4. Proteins
 Are
also called sugars
 Are made up of the elements
C
H O
 Usually,
2H
for every 1 C there are
1 C to 2 H
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The monomers of carbohydrates are
called monosaccharides
Like glucose, fructose & ribose
 The polymers of carbohydrates are
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called polysaccharides
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Like cellulose
 Most
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& starch
carbohydrates have the
ENDING OSE…
Cell walls
(structure)
Cell markers
(communication)
Quick Energy
(Like Glucose)
Stored Energy (Like Glycogen)
4
kcal (dietary calories) per gram
 Foods include bread, pasta, veggies
and fruit
 3 types:
 Monosaccharides
 Disaccharides
 Polysaccharides
 Glucose
 Fructose
 Ribose
 Deoxyribose
 Galactose
 -Saccharide
means sugar
 sucrose
+
 lactose
 maltose
Remember many carbs end in the
suffix -ose
 Starch
 Glycogen
 Cellulose
 Amylose
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Formation of glycosidic bonds
 Dehydration
synthesis (AKA
condensation reaction)- is the
building or SYNTHESIS of
macromolecules with the LOSS of a
water molecule for every bond built.
 Hydrolysis-is
the breaking down of
molecules through the use of water.
For every bond broken, one water
molecule is used.
 Lysis = break
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http://nhscience.lonestar.edu/biol/de
hydrat/dehydrat.html
A
reagent is a chemical compound
used for detecting or identifying other
substances
 We can test for two types of
carbohydrates Monosaccharides and
polysaccharides
Are made up of the elements C H O
 Important lipids, Diglycerides and
triglycerides are made up of subunits
called glycerol (1) and fatty acids ( 2 or
3)
 Most lipids are not made of subunits or
monomers
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 Are
important to all organisms for as
the main part of ALL cell membranes
 Are used as a source of stored
energy
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Are important insulators to help
cushion, keep warm and conduct
impulses
9
kcal (dietary calories) per gram
 Lipids include wax, oil, cholesterol and
animal
fat & many
hormones
This triglyceride
is formed by
building ester
bonds between
the fatty acids
and the glycerol
molecule –
through
dehydration
synthesis
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Saturated fats/lipids contain only
single bonds between carbons
 Unsaturated
fats/lipids have some
double bonds and fewer hydrogens
 (at least one “mono-unsaturated”)
Fatty acids
phospholipid
Steroids
( lipid hormones)
Carbons arranged
into 4 ring structure
Most lipids are extremely HYDROPHOBIC
also known as nonpolar!
Meaning water fearing and do not mix are
insoluble in water
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Made up of the elements C
HONP
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The polymers are DNA (deoxyribonucleic
acid) and RNA (ribonucleic acid) which
includes messenger RNA, ribosomal RNA
and transfer RNA
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Nucleic acids function to store genetic
information, DNA, (directions for making
proteins) or actually direct the building of
proteins, RNA.
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The monomers are nucleotides
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The three parts of the monomer are a
nitrogen base, phosphate group and a
pentose sugar
Monomers
(Nucleotides)
4 for DNA
4 for RNA
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Made up mostly of C, H , O and N
CHON
Function in movement because they
make up muscle and connective tissue
 Are important to all organisms for
structure and shape
 Necessary for all metabolic processesENZYMES
 Important role in immune system –
antibodies
 Our proteins determine who and what
we are!
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Monomers are amino acids
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There are 20 different amino acids
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A protein’s shape is determined by the
arrangement of amino acids
DNA is the instructions for making proteins
in organisms, soooooooooooooooooooooo a mutation means that the protein may
not work!
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Small proteins are often called
polypeptides
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the amino acids that make up a protein are
linked together with covalent bonds called
peptide bonds
4 kcal (dietary calories) per gram
 Foods include egg whites, meat, and fish
 plants contain
limited
amounts
of protein
-Hemolglobin
(in RBC)
-Keratin (in hair)
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neg
pos
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Enzymes regulate and maintain
metabolic functions in ALL living
things. They are essential to life
Enzymes often end in -ase
1.
2.
3.
4.
5.
THEY ARE ALL PROTEINS
They speed up reactions by lowering
the energy of activation (energy
needed to start reaction)
they are specific (only one substrate)
they are reusable (used over and
over)
They are organic catalysts
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The substrate is the specific thing an
enzyme works on
Often are described as lock and key
because how very specific they are
and how they can be reused like a lock
 Necessary
for LIFE
 Often end in –ase More coming soon
 All proteins are sensitive to
change in temperature and pH
 If a protein changes shape, it is
considered denatured and will not
work properly
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The active site is where the substrate fits
into the enzymes
The reactant is what is being changed the
product is what is produced after the
reaction
 Reactants –> Products (reaction)
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 Proteins,
so of course, enzymes are
very sensitive to any thing that can
change their shape, denature them.
 Temperature and pH can DENATURE
proteins so they do not work.
 Genetic defects, changes in DNA,
can produce proteins that do not
work.
http://www.lewport.com/10712041113402793/lib/1071204111340
2793/Animations/Enzyme_activity.html
The pH Scale is used to determine the
acidity and alkalinity (base)
 pH Scale ranges from 0 to 14
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pH is the concentration of H ions
 Acid = pH below 7, The lower the
pH, the stronger the acid as pH
approaches 0
 Neutral = pH of 7pure water
 Base = pH above 7 (alkaline), the
stronger the base is as pH
approaches 14
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