the molecules of life chapter 5, sections 1-4. living things are composed of organic molecules which...

THE MOLECULES OF LIFE

CHAPTER 5, SECTIONS 1-4

Living things are composed of ORGANIC molecules which contain the element CARBON

(INORGANIC compounds do not!)

WHY CARBON?

Carbon has _____ valence electrons and can easily bond with other atoms (including other carbon atoms) to make large, complex molecules in many shapes…

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MONOMERS AND POLYMERS

Most complex macromolecules are POLYMERS which are made up of smaller units called MONOMERS

Polymers are built through a DEHYDRATION reaction where a water molecule is released

Polymer bonds are broken when water is ADDED in a HYDROLYSIS reaction

CARBOHYDRATES

(CH2O)x

Sugars and Starches

Store chemical ENERGY and have some structural purposes

Variable in Size SMALLMONOMER

Monosaccharide Simple Sugars EX: glucose, fructose, galactose

Disaccharide Glucose + Fructose =Sucrose

LARGEPOLYMER

Polysaccharide Many glucose =starch or glycogen, Cellulose

CARBOHYDRATES

HYDROPHILIC molecules (Hydroxyl Group attracts water)

However, POLYSACCHARIDES do NOT dissolve in water because of their size

LIPIDS

Contain mostly Carbon and Hydrogen (some Oxygen)

Fats, Oils, Waxes, and Steroids

HYDROPHOBIC molecules formed from a Glycerol molecule and Fatty Acid Chains (Avoid Water (Don’t Mix)- Nonpolar)

LIPIDS

Store ENERGY and are a structural component of biological MEMBRANES

Saturated Fats (solid at room temp): All carbon atoms single bond

Unsaturated Fats (oils): One or more double-bonded carbon atoms

Steroids (4 fused rings): Circulate as chemical signals (hormones); Cholesterol (Good-HDL/Bad-LDL)

NUCLEIC ACIDS

Contain Carbon, Hydrogen, Oxygen, Nitrogen, and Phosphorous

Molecules of INHERITANCE (DNA and RNA)

Assembled from monomers called NUCLEOTIDES

PROTEINS

Contain Carbon, Hydrogen, Oxygen, and Nitrogen

Made of monomers called AMINO ACIDS (20 different a.a.)

Amino Acids are joined by peptide bonds, therefore another name for a protein is POLYPEPTIDE

There are 4 levels of structural organization

PROTEINS

Proteins are very diverse and have different functions:

Aid in chemical reactions (enzymes)

Help fight disease (antibodies)

Build bone and muscle tissue

Help transport substances in/out of cell

Help regulate cell processes