THE CHEMISTRY OF LIFE
http://www.chem.ufl.edu/~itl/2045_s00/matter/FG01_011.GIF
ATOM: THE SMALLEST UNIT OF
MATTER
• Subatomic particles
• 1. neutron
• a. Inside nucleus
• b. Neutral charge
• 2. proton
• a. Inside nucleus
• b. + charge
• 3. electron
• a. Outside nucleus
• b. Move at speed of light
• c. Have a negative charge
http://www.wjcc.k12.va.us/ROBB/Atom%20Animation%20Resources_files/image003.gif
Atomic Number and Weight
• 1. atomic number- number of protons in nucleus
• 2. atomic weight- number of protons plus neutrons
in the nucleus of the atom (a.k.a. -mass number)
http://www.wisegorilla.com/images/chemstry/PeriodicTable.gif
How many neutrons are in an atom?
Subtract the number of protons from the mass number to
get the number of neutrons
Mass number – atomic number = # of neutrons
FIND THE ATOMIC NUMBER,
ATOMIC MASS, AND # OF
PROTONS, ELECTRONS AND
NEUTRONS OF THE FOLLOWING
ELEMENTS.
Atomic Mass #
#
#
#
#
protons electrons neutrons
Carbon
Hydrogen
Oxygen
ELECTRON SHELLS
• 1. Energy Shells
• a. first level can only
have 2 electrons.
• b. second level can have
8 electrons.
• c. all other levels have 8.
• 2. The chemical behavior
of the atom is
determined by the
atom’s electron shell.
• 3. Valance Electronsoutermost shell
http://static.howstuffworks.com/gif/atom-h-he-li-na.gif
PROBLEM? ALL ATOMS WANT TO
HAVE THEIR VALANCE ELECTRON
SHELLS FULL!
I wish I could be a noble gas!
http://www.csupomona.edu/~egoldstein/121/IMAGES/Periodic_noble.gif
CHEMICAL BONDS
• 1. Making of chemcial bonds Stores Energy.
• 2. The breaking of chemical bonds Releases Energy
Blah blah balh
Sdf
http://faculty.clintoncc.suny.edu/faculty/michael.gregory/files/Bio%20101/Bio%20101%20Lectures/energy/energy12.gif
COVALENT BONDS
• 1. Covalent bond -The
sharing of a pair of
valance electrons by
two atoms.
• 2. Bewteen two
nonmetals
• 3. Can form single,
double and triple bonds
http://www.school-for-champions.com/chemistry/images/bonding_types-water.gif
http://www.roboimages.com/image/ri33813/Care_Bears_Easter.jpg
METHANE: COVALENT BONDS
2. ALL NON-METALS FORM
COVALENT BONDS
• 1. glucose
• 2. water
• 3. carbon dioxide
• 4. sucrose
http://www.peoriaendocrine.com/images/diabetes_lecture/glucose.GIF
http://www.brooklyn.cuny.edu/bc/ahp/SDgraphics/PSgraphics/WaterMolecule.GIF
IONIC BONDS
• 1.One atom transfers
electrons from another to
complete its outer shell.
• Between a metal and
nonmetal
• Example: NaCl
• Because one atom has lost
an electron (Na) it has now
has an overall charge of +1
• Because the atom that took
the electron (Cl) now has an
extra electron, its overall
charge is -1
http://www.sci.sdsu.edu/classes/biology/bio100/truesdale/Lectures%2005/lec2/Image6.gif
4. IONIC BONDING:
http://gcserevision101.files.wordpress.com/2009/02/halogen-ionic-bond.jpg
In a polar covalent bond
Electrons are shared unequally
between atoms, creating a
polar molecule
(–)
(–)
(–)
O
H
(+)
H
(+)
(+)
STRENGTH OF BONDS
• Covalent > Ionic > Hydrogen
WATER IS A MAJOR COMPONENTS
OF CELLS
1. 2/3 of all molecules in the
body (all your cells are
surrounded by water)
2. Water stores heat efficiently.
a. sweating- helps release
heat
b. helps maintain
homeostasis by regulating
temperature
http://www.bigbrandwaterfilter.com/water_filter_images/waterdrop_embossed.gif
Properties of Water
1. Water is the solvent of life (universal
solvent)
- Polar solutes dissolve when water
molecules surround them, forming aqueous
solutions
2. Water is less dense as a solid than a
liquid. Ice floats on water. (Ex. Glacier)
. Hydrogen bonds make water
cohesive (water sticks to water)
ex: Insects can walk on water due to
surface tension (cohesion of water molecules at
the surface of a body of water)
Water is adhesive (water sticks to other
substances)
ex: molecules can move from a plant’s roots to its
leaves (Capillary Action); water moves up a straw
WATER DISSOLVES MANY
SUBSTANCES
• Water is the solvent.
What it is dissolving is
called the solute.
• Solution- mixture in
which one or more
substances is evenly
distributed. Solute and
Solvent together make
a Solution.
http://www.elmhurst.edu/~chm/demos/images/bluebottle.GIF
POLARITY-MOLECULES WITH AN
ELECTRICAL CHARGE
• Water is a polar
molecule
• Only polar molecules
will dissolve in water
• Nonpolar molecules
will not dissolve in
water – Ex: oil
http://colossus.chem.umass.edu/genchem/whelan/class_images/Structure_of_Water.jpg
Water molecules adhere to other polar molecules.
+
HYDROGEN BONDS
-
water molecule
+
+
+
+
-
-
+
+
+
-
-
HCl
hydrogen bond
+
+
+
Hydrogen Bond
1. Occurs when an atom of
hydrogen has a strong
attraction to two atoms
instead of one
2. The atoms must be
highly electronegative
(electron loving) like
Oxygen, Flourine,
Nitrogen, Chlorine and
Bromine
Water has high specific heat.
Specific Heat is the amount of energy
required to change the temperature
of a substance. It allows for moderation
of climate and helps organisms regulate
body temperature.
Water has a high heat of vaporization
(the amount of heat required to convert
liquid water into gaseous water, aka
steam). This makes it an effective
coolant for the body.
That is why sweating
actually cools us
down.
(Evaporative Coolant)
Water has a high boiling point (100 degrees
Celsius)
and low freezing point (0 degrees Celsius)
Water has a neutral pH. Which makes is a
good buffer.
A buffer is a substance that helps to
moderate any changes in pH that result from
the addition of acids or bases.
pH Scale
pH Scale: Based on the
concentration of H+
hydrogen ions
(1-14)
pH of acid <7 (1 – 6.9)
pH of base >7 (7.1 – 14)
pH of neutral = 7
If blood pH is either below
6.9 or above 7.8 a person
cannot survive.
ACIDS AND BASES
• Water can be broken
down into acids and
bases
• Acids1) high concentration
of hydrogen ions (H+);
low concentration of
hydroxide ions (OH-).
2) pH less than 7
EX: HCl
http://www.epa.gov/acidrain/site_students/images/phscale.gif
ACIDS AND BASES
Bases –
1) High concentration of
hydroxide ions (OH-);
low concentration of
hydrogen ions (H+)
2) pH is greater than 7
3) Also called alkaline
EX: NaOH
http://www.btinternet.com/~chemistry.diagrams/ph_scale.gif
PH (2)
More H+
More OH-
ORGANIC COMPOUNDS
• Contain carbon usually bonded to
oxygen, hydrogen,
and other carbon
atoms.
• Most of the matter
in your body is
organic!
• These are
compounds that
usually come from
organisms
http://www.chemistryland.com/ElementarySchool/BuildingBlocks/Jungle500.jpg
Macromolecules
Cells and their organelles are made up
of smaller building blocks called
macromolecules.
There are 4 basic types of
macromolecules. They are:
Lipids
Proteins
Carbohydrates
Nucleic Acids
Monomers & Polymers
Macromolecules are actually made up of even
smaller subunits. Each subunit of a macromolecule
is called a monomer.
The macromolecules themselves are called
polymers, because they are made up of many of
these subunits.
Monomer: one basic unit or
subunit
Polymer: a chain of many
basic units
CARBOHYDRATES
• 1.Made of carbon,
hydrogen, and oxygen
in a 1:2:1 ratio.
• 2. Key source of
energy (sugar) -Found
in fruits and vegetables.
• 3. Monosaccharidessingle (one) sugars,
• A. the building blocks
of carbs
• B. Ends in-ose
• Examples: glucose,
fructose, maltose
http://vienna-doctor.com/images/Pictures/carbohydrates.jpg
Monomer (basic unit) : Simple sugars
or monosaccharides
EX: glucose
Polymer (chain of units): Complex
carbohydrates or polysaccharides
EX: starch, cellulose, chitin, glycogen
DISACCHARIDES AND
POLYSACCHARIDES
• 4. Disaccharides- two
sugars
glucose + fructose =
sucrose
5. Polysaccharides
-a. macromolecule made of
many sugars.
-b. storehouse for energy
Excess Energy is stored as:
-c. starch-in plants
d. glycogen- in animals
e. cellulose-found in plant
cell walls
http://www.pecanbread.com/new/saccharides.jpg
Carbohydrates: Indicator Tests
Simple Sugars:
Benedict’s solution
Blue solution turns
orange/green/brown
Complex Carbs:
Lugol’s
solution/Iodine
Turns from orange-redbrown to black-purple
Let’s Draw a Glucose molecule!
http://www.thefreshloaf.com/files/u12441/alpha-D-glucose%20ring.gif
LIPIDS- ARE NONPOLAR
• Fats, phospholipids, oils,
steroids(cholesterol) and
waxes.
• Fats are lipids that store
energy for long term,
make up the cell
membrane
(phospholipds), provide
cell structure, provide
insulation
http://www.bodybuilding.com/fun/crisco1k.jpg
http://cwx.prenhall.com/bookbind/pubbooks/hillchem3/medialib/media_portfolio/text_images/CH09/FG09_16-05Box.JPG
http://www.healingtouchwebhelp.net/image/heart31.jpg
http://www.chemistryland.com/ElementarySchool/BuildingBlocks/Lipids.jpg
LIPIDS ARE MADE BY COMBINING
TWO TYPES OF MOLECULES
• 1. glycerol
• A three carbon alcohol
• 2. 3 fatty acids
• Long hydrocarbon chains.
• Non polar
The combining of these
two molecules makes a
trigylceride.
http://faculty.clintoncc.suny.edu/faculty/michael.gregory/files/Bio%20101/Bio%20101%20Lectures/Biochemistry/glycerol,%20fatty%20acids,%20triglyceride.gif
LIPIDS: STRUCTURE
• Lipids are made up of…
• C,H,O
• Monomer (basic unit): fatty acids
• Polymer (chain of units): lipids
• Specific examples: triglycerides, phospholipids
LIPIDS: FATS
SATURATED VS. UNSATURATED
Structural
formula of a
saturated fat
molecule
Stearic acid, a
saturated fatty
acid
Structural formula
of an unsaturated
fat molecule
Oleic acid, an
unsaturated
fatty acid
(a) Saturated fat
(b) Unsaturated fat
cis double
bond causes
bending
LIPIDS: INDICATOR TEST
• Paper Bag Test:
• Smear substance onto paper bag
• If see-thru, it contains lipids
PROTEINS: FUNCTION
• Build and repair muscle and tissues
• “No pain, no gain!”
• Enzymes- proteins that speed up chemical reactions
by lowering the activation energy.
• Most enzymes end in –ase.
PROTEINS
• Made of chains of
amino acids
• There are 20 known
amino acids
• These 20 amino acids
are found in all
biological species.
• Collagen-protein found
in skin
• Hemoglobin, blood
clots, and muscles.
http://images.apple.com/science/profiles/proteinfolding/images/proteins.jpg
http://www.cybered.net/library/Teaching_Resources/Biology/Genetic_Engineering/Image_Gallery/GeneticEng-Proteins.jpg
PROTEINS: STRUCTURE
• Proteins are made up of…
• C,H,O,N
• Monomer (basic unit):
amino acids
• 20 different kinds!*
• Polymer (chain of units): protein
• More specifically- polypeptides
Amino
acids
linked by
peptide
bonds
dipeptide
ALL AMINO ACIDS HAVE THE
SAME BASIC STRUCTURE
• 1. alpha carbon- makes
center of amino acid
• 2. amino group
• 3. Carboxyl group- this is
an acid
• 4. a single hydrogen
• 5 . Variable group-R
• There are 20 R groups
• Therefore there are 20
different amino acids in
all living things
http://www.contexo.info/DNA_Basics/images/aminoacidsweb.gif
Let’s draw an amino acid
• 1. draw the alpha
carbon
• 2. put in amino group.
• 3. put in carboxyl
group
• 4. Hydrogen
• 5. R group (variable)
http://www.aloeveraibs.com/wp-content/uploads/2008/08/aminoacidstruc.jpg
PROTEINS: STRUCTURE
• Proteins have complex
structures. The shape of
a protein determines its
function!
• The levels of protein
structure are:
• Primary structure:
polypeptide chain
• Secondary structure:
polypeptides in coils or
sheets
• Tertiary structure: coils or
sheets form a tangle
• Quaternary structure:
more than one tangle
combine to make a very
complex protein!
ENZYME + SUBSTRATE =
PRODUCT
53
SUBSTRATE
• The substance (reactant) an enzyme acts
on. It specifically fits into the enzyme.
Enzyme
Substrate
ACTIVE SITE
• Where the substrate and the enzyme fit
together and bind to activate the enzyme.
Substrate
Enzyme
Active Site
Enzymes
• Are specific
for what
they will
catalyze
• End in -ase
Enzymes are specific, like a
lock & key
Enzyme – Substrate
Complex
ENZYMES ARE BIOLOGICAL
CATALYSTS
http://www.staff.uni-mainz.de/lieb/tierphys/enzyme.gif
ENZYMES AFFECT SPECIFIC
SUBSTANCES.
http://library.thinkquest.org/3659/orgchem/lock-key-enzyme.gif
http://www.blc.arizona.edu/courses/181summer/graphics/graphics%20lect7/Life7e-Fig-06-10-0%203D%20fit%20of%20enzyme%20and%20substrate.jpg
ENERGY IS NEEDED TO START A
CHEMICAL REACTION.
• 1. Activation energythe energy needed to
start a chemical
reaction.
• 2. Chemical push!
http://www.colorado.edu/intphys/Class/IPHY3430-200/image/04-3.jpg
ENZYMES HELP BIOCHEMICAL
REACTIONS OCCUR.
• A. allows reactions to
occur quickly and at low
temperatures.
• B. increases the speed of
chemical reactions.
• C. most are proteins.
• D. act as catalysts-reduce
the amount of activation
energy required.
• E. helps maintain
homeostasis.
http://w3.dwm.ks.edu.tw/bio/activelearner/06/images/ch06c1.jpg
THREE THINGS THAT EFFECT
ENZYME ACTION.
• 1. amount of enzyme concentration
• 2. Temperature
• 3. pH
PROTEINS: INDICATOR
TEST
• Biuret’s Solution:
• Turns from blue to purple if protein is present
NUCLEIC ACIDS:
FUNCTION
• Stores and carries genetic information
NUCLEIC ACIDS: STRUCTURE
• Nucleic Acids are made up of…
• Made up of C,H,O,P, N.
• Monomers (basic unit): nucleotides
• Polymers (chain of units): DNA or RNA
NUCLEIC ACIDS
http://www.duke.edu/web/MAT/jennifer_sohn/unit/images/what_is_rna1.gif
• Made of nucleotides.
• Nucleotides contain a
sugar, phosphate and a
nitrogen base.
• DNA-double stranded
and makes up
chromosomes
• RNA-single stranded,
used in making
proteins.
DNA AND RNA
http://images2.clinicaltools.com/images/gene/dna_versus_rna_reversed.jpg
ATP-ADENOSINE TRIPHOSPHATE
• Energy currency for the
cells.
• Cells need a constant
supply of ATP to
function.
http://www.colorado.edu/epob/academics/web_resources/cartoons/atp.gif
ORGANISMS NEED ENERGY FOR
LIFE PROCESSES
• Energy- the ability to move
or change matter.
• A. Energy is stored and
released by chemical
reactions.
• B.Reactants and products
• Chemical reaction absorb
and release energy
• 1.Freezing water releases
energy
• 2.Melting ice absorbs energy
http://www.windows.ucar.edu/teacher_resources/activities_3x3.jpeg
ATP
• ATP = ENERGY
• ATP has 3 phosphates, a sugar (ribose), and adenine
• Energy is released when the 3rd phosphate bond
breaks.
• This leaves ADP and a “free phosphate.”
ATP – ADP Cycle
1. ADP joins
together with
a free
phosphate
gained
through
energy from
food. This
makes ATP.
2. Then ATP releases energy for cells by breaking
the 3rd phosphate which makes ADP and a free
phosphate.