Transcript Biomolecules - Greater Clark County Schools

BIOMOLECULES
Biology Fall 2009
DESK-OMERS
 Please
 We
stand around your desks.
will have a DMA after the
demonstration.
POLYMERS
 Poly-mer
means “many units.”
 Polymers
are large molecules formed of
smaller repeating molecules.
 They
often form long chains, just like
your desks.
MONOMERS
 Monomers
are small molecules that
chain together to form polymers.
 Each
individual desk was like a
monomer in the larger Desk-omer.
 There
can be anywhere from 3 to
thousands of monomers in a single
polymer and these small units dictate
the shape of the overall polymer.
“ORGANIC”
 Polymer
and their monomers are
considered organic molecules.
 Organic
refers to a chain of carbon
atoms linked together by Covalent
bonds- the sharing of electrons.
 Biomolecules
are organic because of
their carbon chains, but not all organic
molecules are biomolecules.
BIOMOLECULE TYPES
 There
are four distinct types of
biomolecule polymers:
 Carbohydrates: Storage and cellular
support
 Lipids: also known as fats; storage and
cell membranes
 Proteins: Pick a function, any function,
proteins will be involved somewhere
 Nucleic Acids: These molecules contain
the information that allows a cell to
function
EXAMPLES

Carbohydrates



Polymer: Starch
Monomer: Glucose
Lipids
Polymer: Phospholipid
 Monomer: Fatty acids and Glycerol


Proteins



Polymer: Pepsin Enzyme
Monomer: Amino Acids (e.g. Methionine)
Nucleic Acids


Polymer: Chromosome
Monomer: Deoxyribonucleic Acid (DNA)
OTHER POLYMERS
DON’T WRITE THIS DOWN
 Plastics
are the most common polymer
outside of biomolecules.
 Plastics
are manufactured, with the
exception of natural rubber.
 Just
like biomolecules, plastics are
composed of monomers such as styrene,
ethylene and isoprene.
VIDEO
 This
doesn’t have to do strictly with
polymers, but it is interesting.
 http://www.teachertube.com/viewVideo.
php?video_id=64710&title=Polymer_Ban
k_Notes___How_they_are_made
QUIZ
Please
put everything away
except something to write
with.
CARBOHYDRATES


Monomer: Small sugars, usually glucose
or something very close.
: CXHYOZ
Formula
DISACCHARIDES
 “Di”
means 2. And Saccharide is a sugar.
 Sugar that we put in baked products is
actually a disaccharide called Sucrose.
 Sucrose is the combination of Glucose
and another single sugar called Fructose
(Fruit sugars).
 Lactose, the sugar in milk is also a
disaccharide.
 Single sugars are also called
monosaccharides.
STARCH
 Primarily
in plants, but also used in
animals for storage.
STARCH
 Starch
is a storage molecule, unused
sugar monomers are assembled and kept
until the sugar is needed.
Structure is related
to function, branching
helps to save space.
CELLULOSE
 Cellulose
makes up most of the hard
structures in plants. It’s the reason cell
walls don’t bend and trees are able to
stay in the air.
CELLULOSE


Like starch, Cellulose has a structure
closely related to its function.
Cellulose doesn’t branch at all, it relies
on the straight chain of monomers and
the alternating of protruding OH
groups to maintain strength in tight
bundles.
GLUCOSE BUILDING ACTIVITY
 To
get an idea of the complexity of
biomolecules, we’re going to assemble
glucose molecules in table groups.
 Please
have one person grab a molecule
kit for each table.
GLUCOSE MOLECULE ACTIVITY

You’ll need:
6
Carbons [Black]
12 Hydrogens [Yellow]
6 Oxygens [Red]
GLUCOSE
JUST THINK
 As
a class we’ve put together less than
20 glucose molecules and there can be
hundreds of small monomers in starch
and cellulose.
LIPIDS
 Fats
and Oils, easily the oddest of the
biomolecules. Unlike the carbohydrates,
Lipids don’t make chains of monomers.
LIPIDS
 Monomers:
 Formula:
Glycerol and Fatty Acids.
CXHYOZ (For the most part)
 Just
like Carbohydrates, the formula
consists of only CHO, but there are
always more than 2 times as many H as
O.
 Example:
C6H12O6 vs C6H18O6
TRIGLYCERIDES
 The most common form of Lipids in animals, this is
the form excess calories take once the body has
converted them to storage.
 Excess levels
in the blood can
lead to Heart
Disease and can
be an indicator of
problems to come.
PHOSPHOLIPIDS
This is the lipid that we will deal with the most in
chemistry.
 It has all the parts of a normal lipid, but has a
“head” region with a
phosphate group that
makes the molecule
polar.

PHOSPHOLIPIDS

Phospholipids make up nearly all cell
membranes, the phosphate “heads” face outward,
while the non-polar tails face inwards.
PROTEINS
 Monomers:
Amino Acids, 20 molecules of
various sizes.
 Formula:
 The
CHON and maybe S
structure of every protein depends
upon the make-up of amino acids and
how they react to each other and the
environment.
PROTEINS
PROTEINS
 Proteins are found everywhere.
 Proteins make up our hair, skin, nails, organs and
muscles.
 The enzymes that carry out the processes in our
cells are all proteins.
 Proteins carry out almost every action in both
plants and animals.
AMINO ACIDS
 There
are 20 different amino acids.
 They
are assembled via instructions
encoded in our DNA and can form
chains thousands of amino acids long.
The structure of every amino acid varies
and those differences contribute to the
shape of the overall protein.
ESSENTIAL AMINO ACIDS
8
out of the 20 amino acids cannot be
made by human cells.
 This means they have to be taken in as
part of the diet.
 Methionine, Leucine, Lysine, Isoleucine,
Tryptophan, Threonine, and Valine are
all found in meats, eggs and milk.
 Vegetarians must be careful to eat a
combination of protein sources (Such as
Soy, Sesame and Wheat).
NUCLEIC ACIDS
 Monomers:
Nucleotides [Adenine,
Guanine, Cytosine, Thymine & Uracil]

Formula:
CHONP
 Nucleotides
are linked in
pairs (in DNA) and form a
twisted ladder-like formation
known commonly as “double helix.”
THE DOUBLE HELIX
 This
is an artist’s
representation of
the DNA
“double helix.”
 The
only
inaccuracy is that it
should twist slightly
more. DNA twists
every 10 nucleotide pairs, not every 15.
THE BLUEPRINTS
 DNA nucleotides encode all the information for
creating our cells.
 These nucleotides form, when read in a particular
direction, a sequence that stands for the individual
amino acids in a protein.
ANATOMY OF A NUCLEOTIDE
 Each
nucleotide has 3 parts to it.
 The phosphate group and sugar form
what is considered the “backbone” and
is part of all nucleotides.
 The “nitrogenous
base” can be any of 4
different structures and
makes up our genetic
Information.
DNA VS RNA
 This
is something we’ll go over in more
detail when we talk about genetics.
 RNA is a nucleic acid just like DNA.
 The only difference is the sugar
molecule in the backbone is slightly
altered and it uses one nitrogenous base
that DNA doesn’t.
 Analogy: If DNA is the Post Office, RNA
are mailmen carrying the message to
where it needs to go.
ENERGY CARRYING MOLECULE

AMP, ADP, and ATP: These are the “batteries”
for cell activities. The M, D, and T represent the
number of phosphates in the molecules.
BIOMOLECULE CARD ACTIVITY
 Please
take out a new piece of paper,
and make a 4x5 grid
Biomolecule
Type
Name or
example of
Monomer
Carbohydrate
Simple Sugar
(Macromolecule)
Lipid
Protein
Nucleic Acid
Picture of
monomer
Made of /
functions,
and
examples
CHO, Energy
Disaccharide
Starch
BIOMOLECULE CARD ACTIVITY
 Each
group will be given a set of cards.
 When arranged correctly they should
form a sort of grid or table matching the
biomolecule types with examples,
monomers, structures, etc.
 Using your notes, table groups will try
to put the cards in the right order.
 Raise your hands when you think you’ve
got it right, once you have it checked off
you need to write it down as a table on
that fresh piece of paper.
ACIDS AND BASES
 Take
out a piece of paper and fold it in three
sections
 Like this
Know

Top
Want
Learn
Bottom
ACIDS
 Acid
comes from the Latin word for
sour.
 Just about anything sour you can think
of is an acid or has an acid in it.
 Acids are chemicals that release positive
Hydrogen ions
 The most common acid we’ll look at is
Hydrocloric Acid or HCl
 When in water HCl splits into H+ and Cl-
BASES
 Bases
are a little more complicated.
 Bases are chemicals that steal Hydrogen
Ions.
 NaOH is the most common base that
we’ll talk about.
 In water it splits into Na+ and OH- , the
OH- can bond with an H+ ion to become
a water molecule.
 This is why we pour baking soda(a base)
on acid spills.
PH SCALE
This is a “user –friendly” way of rating
acids and bases in terms of strength.
 Most often the scale is represented from 114.
 7 represents a neutral solution like pure
water.
 Anything less than 7 is considered acidic
(the closer to one the stronger).
 Anything greater than 7 is considered basic
(the closer to 14 the stronger).
 The scale is a logarithm for concentration,
pH 7 = 1x 10-7 moles/Liter H+. Obviously we
like pH 7 better.

EXAMPLE PH SCALE
1
Stomach Acid
11 Ammonia
 2 Lemon Juice, Vinegar 12 Soapy Water
 3 Orange Juice, Soda
13 Bleach
 4 Tomato Juice, Acid Rain
14 Drano
 5 Coffee
 6 Urine/Milk
 7 Pure Water
 8 Sea Water/ Eggs
 9 Baking Soda
 10 Milk of Magnesia
THE “TEN RULE”
 Every
step in the pH scale is 10 times
more or less acidic than the next.
 Lemon
Juice is 10 times as acidic as
Orange Juice
 Sea
water is 10 times less acidic (or
more basic) than pure water
OOOOH BURN!
Acids don’t burn you the way a match or a
hot surface will.
 An “acid burn” isn’t really a burn at all. It
just happens to look like a heat burn.
 The acid chemicals actually react with your
skin, in some cases pulling bonds in your
skin apart. In some cases pulling an OH out
of a compound. Sometimes it isn’t even the
H+ of the acid.
 Even though an acid burn isn’t technically
a “burn” they still hurt and should be
washed immediately and treated like one.
