Macromolecules
• All compounds on earth can be classified in 2
broad categories:
– 1. Organic compounds- contains carbon and
hydrogen atoms
– 2. Inorganic compounds- can have one or the
other, but do not contain BOTH carbon and
hydrogen atoms
Macromolecules
• Most of your body’s molecules are ORGANIC!
– Macromolecules are built from small organic
compounds the same way a railroad train is built,
by linking a lot of smaller unit together into long
chains.
Macromolecules
• Large carbon compounds are built up from
smaller simpler molecules called monomers
(mono = ONE)
Macromolecules
• Monomers can bind to one another to form
complex molecules known as polymers (poly =
MANY)
Macromolecules
• A polymer consists of repeated, linked units,
which can also bind forming large polymers
called macromolecules (macro = LARGE)
• Monomers link to form polymers through a
chemical reaction called dehydration
synthesis. During the formation of polymers,
water is released or is a by-product.
Dehydration Synthesis
Macromolecules
• The breakdown of some complex molecules,
such as polymers, occurs through a process
known as hydrolysis. This is the reverse of a
condensation reaction or dehydration
synthesis. The addition of water can break the
bonds that hold polymers together.
Hydrolysis
Type of Macromolecules
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1. Carbohydrates
2. Lipids
3. Proteins
4. Nucleic Acids
Carbohydrates
• Composed of carbon (C), hydrogen (H), and
oxygen (O) atoms in the proportion of 1:2:1
– Example: The sugar glucose is a small
carbohydrate; its chemical formula is C6H12O6
Carbohydrates
• The building blocks, monomers, of carbs are
called monosaccharides. Monosaccharides
are simple sugars.
– Examples:
• Glucose- commonly found in the blood of animals
• Galactose- a simple sugar found in milk
• Fructose- commonly found in fruit
Carbohydrates
Carbohydrates
• Disaccharides contain two monosaccharides
joined during dehydration synthesis.
– Examples:
• Lactose- commonly found in milk and is made of
galactose and glucose
• Sucrose- commonly known as table sugar and is made
of fructose and glucose
Carbohydrates
Carbohydrates
• Polysaccharides are carbohydrates formed
from linking of individual sugars into long
chains.
– Examples:
• Starch- a common storage form of glucose in plants
• Cellulose- found in the cell walls of plants; gives the
plant strength and structure
• Glycogen- a common storage form of glucose in
animals (used for quick energy)
Carbohydrates
Lipids
• These include fats, oils, waxes, and steroids
• Do NOT dissolve in water (nonpolar)
• Usually serve one of three functions:
– 1. long term energy storage
– 2. structural support in cell membranes
(phospholipids)
– 3. protection and insulation (especially in
animals)
Lipids
• Fatty acids are the building blocks, or
monomers, that make up most lipids.
• Fatty acids can be saturated or unsaturated
Proteins
• Proteins are organic compounds mainly
composed of carbon (C), hydrogen (H), and
nitrogen (N) atoms.
• Proteins are the construction materials for
body parts such as hair, skin, nails, and blood.
• Amino acids are the building blocks,
monomers, that make up proteins. The
individual amino acids are held together by
peptide bonds.
Proteins
Proteins
• One important group of proteins, enzymes,
help control chemical reactions by acting as
catalysts. Catalysts speed up reactions be
lowering activation energy.
Nucleic Acids
• Nucleic acids are complex organic molecules
that store genetic information in the cell.
• Nucleotides are the building blocks,
monomers, that make up most nucleic acids.
Nucleic Acids
• Nucleotides consist of a sugar, phosphate, and
a nitrogen base
– Example: DNA nucleotide
Nucleic Acids
• Three main types of nucleic acids:
– 1. DNA: deoxyribonucleic acid; this is the genetic
information inside the nucleus of all cells
– 2. RNA: ribonucleic acid; instructions which code
for proteins
– 3. ATP: adenosine triphosphate; used as energy
for the cell