Transcript The Structure and Function of Macromolecules

The Structure and
Function of
Macromolecules
I. Polymers
• What is a polymer?
• Poly = many; mer = part. A polymer is
a large molecule consisting of many
smaller sub-units bonded together.
• What is a monomer?
• A monomer is a sub-unit of a polymer.
A Polymer
Here are some analogies to better
understand what polymers and monomers
are….
EXAMPLE of
POLYMER
A TRAIN
A NECKLACE
MONOMER
THE CARS
EACH PEARL
A. Making and Breaking
Polymers
• How are covalent bonds between
monomers formed in the creation of
polymers?
• Dehydration synthesis reactions.
• Monomers are linked to one another
through the removal of water.
Dehrdration Synthesis
Hydrolysis
• What is a hydrolysis reaction?
• Polymers are broken down into
monomers.
• Hydro = water; lysis = loosening/
• Water is added and the breaking or lysis
of the polymer occurs.
Hydrolysis
II. Classes of Organic
Molecules:
• What are the four classes of organic
molecules?
• Carbohydrates
• Lipids
• Proteins
A. Carbohydrates
• Sugars
• Carbo = carbon, hydrate = water;
carbohydrates have the molecular
formula (CH2O)n
• Functions:
• Store energy in chemical bonds
• Glucose is the most common
monosaccharide
• Glucose is produced by photosynthetic
autotrophs
CARBOHYDRATES
THERE ARE 2 TYPES OF
CARBOHYDRATES
Simple
Complex
1. Structure of
Monosaccharides
• An OH group is attached to each carbon
except one, which is double bonded to
an oxygen (carbonyl in pink).
Simple Sugars are
carbohydrates
made up of 1 or 2 monomers.
They also taste sweet.
Simple Sugars
Complex
Carbohydrates…
What are they?
Complex Carbohydrates are polymers
made up of many monomers.
Most also taste starchy
Complex Carbohydrates
• Classified according to the size of their
carbon chains, some examples vary
from 3 to 7 carbons.
Triose = 3 carbons
Pentose = 5 carbons
Hexose = 6 carbons
2. Structure of Disaccharides
• Double sugar that consists of 2
monosaccharides, joined by a glycosidic
linkage.
• What reaction forms the glycosidic
linkage?
• Dehydration synthesis
Examples of Disaccharides:
Lactose = glucose + galactose
Sucrose = glucose + fructose
3. Polysaccharides
• Structure: Polymers of a few hundred or a few
thousand monosaccharides.
• Functions: energy storage molecules or for structural
support: These are examples:
• Starch is a plant storage from of energy, easily
hydrolyzed/broken down to glucose units (sugars) Ex:
Potato, corn, wheat, etc.
• Cellulose is a fiber-like material - tough and insoluble used in plant cell walls. We can’t break it down.
(1,000’s of sugars long)
• Glycogen is a highly branched chain used by animals
to store energy in muscles and the liver. Released from
your liver when you get scared. So much energy in it
that your hands shake when you are scared, or have
adreneline. Sits in your muscles so you can run if
needed.
• Chitin is a polysaccharide used as a structural
material in arthropod and crustacean exoskeletons.
B. Lipids
• Structure: Greasy or oily nonpolar
compounds
• Functions:
• Energy storage 9 calories per gram
• Cell membrane structure
• Protecting against desiccation (drying out).
• Insulating against cold. Fat.
• Absorbing shocks, in joints, and around
organs
1. Structure of Fatty Acids
• Long chains of mostly carbon and hydrogen
atoms with a -COOH group at one end.
• When they are part of lipids, the fatty acids
resemble long flexible tails.
Saturated and Unsaturated Fats
• Unsaturated fats : Good
– liquid at room temp
– one or more double bonds between carbons in the
fatty acids allows for “kinks” in the tails. Tails are
bent and can be broken down. Don’t get caught in
arteries.
– mostly plant fats; Olive oil, Canola, Corn oil, etc
• Saturated fats: Bad for you
– have only single C-C bonds in fatty acid tails. Lots
of Hydrogen bonds– body can’t break them down
– solid at room temp
– mostly animal fats; butter, red meat fats,
Saturated fatty
acid
Saturated fatty
acid
Lots of Hydrogens
Unsaturated
fatty acid
Has double
bonds
3. Phospholipids
• Structure: Glycerol + 2 fatty acids + phosphate group.
• Function: Main structural component of membranes, where
they arrange in bilayers.
C. Proteins
• Structure:
• Polypeptide chains of Amino Acids
• Consist of peptide bonds between 20
possible amino acid monomers
• Have a 3 dimensional globular shape
• Each Protein has a specific order and number
of Amino Acids
1. Functions of Proteins
• Enzymes are proteins which accelerate
specific chemical reactions in the body
up to 10 billion times faster than they
would spontaneously occur.
• Structural materials, including keratin
(the protein found in hair and nails) and
collagen (the protein found in
connective tissue).
• Antibodies are proteins that bind
specifically to foreign substances to
identify them to the body's immune
system.
• Blood proteins, such as hemoglobin,
that carry oxygen, iron, and other
substances through the body. Muscles,
Hormones, and Neurotransmitters in the
Nervous system.
• Contraction, such as actin and myosin
fibers that interact in muscle tissue.
• Signaling, including hormones such as
insulin that regulate sugar levels in
blood.
Each of these is an Amino Acid. Bound together
in order to make a protein.
Summary of the Organic
Molecules: