Transcript Macromolecules Power Point

Carbon Compounds
“Macromolecules”
Protein
Lipid
Carbohydrates
The Chemistry of Carbon
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Is known as organic chemistry
Carbon is very light and versatile.
It has 4 valence electrons.
It can easily form strong covalent bonds
with H,O, N, and several other biologically
important atoms such as P and S.
It can form single, double, or triple bonds.
It can form chains and rings. (Catenization)
It can form millions of different molecules of
varying size and shape.
Macromolecules
• Macromolecules are molecules that are
made of many atoms. [BIG molecules]
• They contain specific functional groups
that give them their characteristics.
• Many macromolecules are made by
combining already large macromolecules
(monomers) into even larger
macromolecules called polymers.
• Polymerization – monomer molecules are
combined into much larger polymer
molecules.
Macromolecules, cont.
• Repeating numbers of smaller units, monomers,
join together (sometimes hundreds of thousands
sequenced or clustered) to form polymers.
• The four groups of organic macromolecular
compounds we discuss in biochemistry are
are polymers made of monomers:
– Nucleic acids (from nucleotides)
– Proteins (polypeptides from amino acids)
– Carbohydrates (polysaccharides from
monosaccharides)
--Lipids (fat is an example and not a true
polymer but it is from a combination of glycerol
with 3 fatty acid molecules)
Biochemistry
• The branch of organic
chemistry that deals with the
reactions involving
monomers and polymers
created within living things.
Carbohydrates
• Monomer: monosaccharide (simple
sugars)
– Glucose, galactose, fructose
• dimer: disaccharide (double sugars)
- sucrose, lactose, maltose
• Polymer: polysaccharide (complex carbs)
- Glycogen, chitin, starch, cellulose
• Made up of:
– C, H, O (in a 1:2:1 ratio)
Carbohydrates, cont.
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Functions:
– Living things use carbohydrates as their main source of energy.
– Plants and some animals use carbohydrates for
structural purposes
Examples:
– Glycogen= animals store excess sugar as glycogen in muscles &
liver to store the energy of glucose.
– Cellulose= Fibers that give plants much of their strength and
rigidity (insoluble & indigestible by most organisms)
– Chitin=
animals use this to build structures such as arthropod
exoskeletons (insects, crabs, etc…)
– Starch= Plants use this to build structures such as arthropod
exoskeletons (insects, crabs, etc…)
Indicator Test:
– Monosaccharide (Monomer) = Benedicts
+ test changes from blue to green, orange or red when heated
– Polysaccharide (Polymer) = Iodine Solution
+ test changes from brownish to dark blue/black (deep
purple)
Lipids
• Lipids are the only macromolecules that are
not truly a polymer. (we will consider each of the
three fatty acids and glycerol to be monomers
and fat to be the polymer)
• Fats and Oils are made up of glycerol and 3 long
chained fatty acids. (saturated or unsaturated)
• Steroids such as cholesterol and testosterone
• Carbon, Hydrogen, and Oxygen
are in a 1 : 2 : few ratio
Lipids, cont.
• Functions:
– Store energy
– Make up biological membranes and
waterproof coverings
• Examples:
– Fats
– Oils
– Waxes
– Steroids (hormones such as testosterone &
estrogen and important animal cell membrane
component we call cholesterol.
• Indicator Test: Brown paper bag or Sudan (IV)
+ test is a transparent paper bag or red stained fat
globules
Lipids, cont.
• Lipids can be saturated or unsaturated.
– Saturated = carbon atoms are
bonded to as many hydrogen atoms as
possible. Solid at room temperature.
– Unsaturated = some of the carbon
atoms have double bonds to other
carbon atoms. Liquid at room
temperature.
Proteins
• Monomer: amino acids (20 different kinds of aa)
- Compound with an amino group on one end and a
carboxylic acid group on the other.
- a peptide bond forms between the amino group of one
aa and the acid group of another aa forming a dipeptide.
• Polymer: proteins (or polypeptides)
• Millions of possible proteins can be formed by changing
the length and sequence of amino acids. analogy 26
letters in the English alphabet produce nearly a million
words. 20 amino acids produce millions of kinds of
proteins.
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Made up of: C, H, O, N (and sometimes S) atoms
Proteins, cont.
• Functions:
– Control the rate of reactions and regulate cell
processes.
– Form bones and muscles.
– Transport substances into or out of cells.
– Help fight disease.
• Examples: (proteins end in –ase, -en, -in)
– Enzymes (catalase destroys H202)
– Casein (milk protein in mammals)
– Collagen & Elastin
– Keratin (ex. scales, feathers, hair)
– Found in meats, nuts, gelatin
• Indicator Test: Biuret Test
– (positive goes from Blue to lavender)