Macromolecules

Two types of reactions Monomers and Polymers

Overview of CarbohydratesOverview of Lipids

Overview of ProteinsOverview of Nucleic Acids

Organic Macromolecules Four Groups: Carbohydrates Lipids Proteins Nucleic Acids

Reactions in Living Things Catabolic Reactions: Those that break

macromolecules into smaller molecules and release energy in the process.

Anabolic Reactions Those that make smaller

molecules into macromolecules and use energy in the process.

Monomers Polymers Small or single units In sugars the

monomers are monosaccharides

In lipids,none* In proteins, amino

acids In nucleic acids,

nucleotides

Many monomers put together

In sugars the polymers are polysaccharides

In lipids, lipids In proteins, proteins In nucleic acids,

nucleic acids (DNA or RNA or ATP)

Building Up & Breaking Down Anabolic Reaction called

Dehydration Synthesis (means “lose water to make”) makes polymers from monomers.

Catabolic Reaction called Hydrolysis (means water destruction) makes monomers from polymers.

Examples Monosaccharide +

monosaccharide is made into a disaccharide and a molecule of water is made in the process. (see text picture)

Disaccharide is broken using a water molecule into monosaccharide +monosaccharide

Dehydration Synthesis

Hydrolysis

Carbohydrates Sugars and starches are important fuel

sources for the human body as well as making up structures in the body like cell membranes.

Sugars are grouped by how many carbon atoms they have and their names end in -ose. A triose sugar has 3 carbons, etc.

Glucose is the main sugar that powers cells like those in your brain.

Carbohydrates are the primary source of fuel for your body. Any that are not used are then converted to amino acids, fatty acids, etc.

Functions of Polysaccharides Polysaccharides are polymers of sugars. Composed of hundreds of

monosaccharides joined by glycosidic linkages.

Storage polysaccharides include: starch stored as granules in plastids

of plants glycogen stored by animals in liver

and muscle cells

Polysaccharide Functions cont. Structural polysaccharides include: cellulose in which the beta configuration

of glucose forms a strong fiber that is used all over the world. (wood, rope, etc.)It also aids the digestive systems of animals.

chitin is a carbohydrate used by insects and related animals as an exoskeleton. It is also used as building material for the cell walls of fungi.

Lipids Consist mainly of hydrocarbons Have little or no affinity for water Store large amounts of energy * do not really have monomers

although some will say their monomers are fatty acids

Large molecules

How a Lipid is Constructed Formed from smaller molecules by

dehydration synthesis Usually composed of fatty acids and a

glycerol (see diagrams) Glycerol is an alcohol with 3 carbons-each

having a hydroxyl group (OH) Fatty acid is a long hydrocarbon chain

with a carboxyl group They vary in length and position of double

bonds.(saturated fats= more hydrogen)

Lipid Behavior Lipids are soluble in NONPOLAR

solvents and insoluble in polar solvents (water).

Hydrophobic parts of lipid molecules cause characteristic formations like micelles and cell membranes to form.

Heads have an affinity for water and tails are hydrophobic.

Lipid Functions Lipids function as insulators and

energy storage in the bodies of animals.

Structurally they form cell membranes (phospholipid bilayer)

Proteins Composed of monomers called amino acids

(or peptides) Diverse in structure and function (see chart

in text) Exhibit simple to complex structures that

allow various functions (Primary to Quaternary)

Folding of proteins is intensely studied because the genetic code makes proteins. The more we know about proteins, the more we will know about our genetic code.

Amino Acids Amino acids are composed of: Amino group Carboxyl group Hydrogen atom ( and asymmetric

carbon) Variable group (R group) which varies

with the amino acid and determines the unique characteristics of each amino acid.

They are linked by a covalent peptide bond. Essential amino acids are those that cannot by

synthesized by the body.

Protein Structure Primary structure is a chain-the amino acid

sequence of a polypeptide. Secondary structure is the shape in a

localized region of a polypeptide molecule. Tertiary structure is the overall

conformation or shape of a polypeptide molecule.

Quaternary structure refers to the spatial or conformational relationship between two or more polypeptide molecules that make up a protein.

Nucleic Acids Composed of nucleotides which

themselves are composed of: pentose sugar nitrogen base phosphate group Pentose sugar can either be ribose or

deoxyribose. Nitrogen bases can occur as single rings

(pyrimidines) or double rings (purines)

Nucleic Acid Functions Nucleic acids function as information

storage(DNA and RNA) and energy transfer compounds(ATP).

Information storage is in the sequence of the nitrogen bases on the DNA molecule.

ATP is an adenine nucleotide with 2 additional phosphate groups attached. It is the breaking of the bonds that creates energy used in the cell.