Download Biological Molecules - Fall River Public Schools

The building block of life.
 All
living and once-living things are
made up of the element carbon
 Carbon is unique because it can make up
to four strong covalent bonds
• Bonds can be single, double, or triple bonds
 Carbon
compounds form 3 main shapes:
A
single chain or ring is called a
monomer
 Many monomers can join together to
make a large “macromolecule” called a
polymer
 A reaction that combines two or
monomers is called a condensation
reaction
• H2O is also produced through condensation
reactions
• Also called dehydration synthesis
 The
opposite of dehydration synthesis is
hydrolysis
• Water (H2O) is added to a polymer and breaks
the bonds linking two monomers together
• http://www.biotopics.co.uk/as/disaccharidehyd
rolysis.html
 Carbohydrates
are compounds made of
carbon, hydrogen, and oxygen in a 1:2:1
ratio (example: CH2O, C6H12O6)
 All living things use carbs as their main
source of energy
• Plants use starch
• Animals use glycogen
 Carbohydrates
cells
are also used for structure in
• Plants have cellulose in their cell walls
• Fungi have chitin in their cell wall and insects have
chitin in their exoskeletons
 Carbohydrates
are sugars, or
saccharides
 A single sugar molecule is called a
monosaccharide
• Glucose is a very important monosaccharide
and makes up many more complex sugars
• Other examples of monosaccharides include:
 Sucrose – table sugar
 Lactose, found in milk
 Fructose, found in most fruits
 Many
monosaccharides linked together
are called polysaccharides
• Starch, glycogen are long chains of glucose
molecules
• Cellulose and chitin are also polysaccharides
 Proteins
are made up of the elements
carbon, hydrogen, oxygen, nitrogen, and
sulfur
 Proteins are polymers of molecules
called amino acids
• More than 20 different amino acids exist in
nature
http://www.biotopics.co.uk/as/aminocon.html
 Proteins
have four main shapes
• Straight chain of amino acids
• Chain with twisted amino acids
• Twisted and folded chain
• Knotted chain
 Protein
chains are connected by two
bonded sulfur atoms, called disulfide
bridges
 Proteins
control the rates of reactions and
regulate cell processes (enzymes)
 Proteins also provide structure within living
things
 Examples:
• Collagen makes up cartilage, tendons (muscles),
skin, and bones
• Keratin makes up horns, feathers, hair, and finger
nails
• Enzymes increase reaction rates
 Carbonic anhydrase quickly removes carbon dioxide from
the bloodstream
 Lactase breaks down lactose
 Lipids
are made up of carbon, hydrogen,
oxygen, and phosphorous
 Lipids are fats, oils, waxes, and steroids
 Lipids are made up of a glycerol
backbone and fatty acid chains
GLYCEROL
FATTY ACIDS

A saturated fatty acid is a
fatty acid chain where all
carbons are linked by
single bonds
• Saturated fats are solids at
room temperature

An unsaturated fatty acid is
a fatty acid chain where
there is at least one double
bond between two carbon
atoms
• The fatty acid chains are
bent where there are double
bonds
• Unsaturated fats are liquids
at room temperature
 Lipids
are used for long-term energy
storage
• Fats are used for energy storage
 Lipids
are also used in cell membranes
and to deliver chemical messages
• Phospholipids make up cell membranes
• Steroids include hormones, which deliver
chemical messages, and cholesterol
• Waxes include ear wax, beeswax, and the
waterproof wax coating on plant stems and
leaves
 Nucleic
acids are made up of carbon,
hydrogen, oxygen, phosphorous, and
nitrogen
 Nucleic acids are made up of nucleotides
 Nucleotides are made up of
• 5-Carbon sugar – deoxyribose (DNA) or ribose
(RNA)
• Nitrogen base – A, T, G, C, or U
• Phosphate group
 Nucleic
Acids store genetic information
(DNA) or synthesize, or put together,
proteins (RNA)
 The order of the nitrogen base pairs
determine genetic code
• DNA has adenine (A), guanine (G), thymine (T),
and cytosine (C)
• RNA has A, G, C, and uracil (U) instead of T
• A always joins T or U and G always joins C
DNA HAS A DOUBLE HELIX
SHAPE
RNA HAS A SINGLE HELIX
SHAPE