Chemistry of Life
How do macromolecules effect living things?
Notes: Carbon Compounds
 https://www.youtube.com/watch?v=IJ7xOSCEmZw&list=PLwL0Myd7Dk1F0i
QPGrjehze3eDpco1eVz
The Chemistry of Carbon
 Carbon can bond with many elements, including hydrogen, oxygen,
phosphorus, sulfur, and nitrogen to form the molecules of life.
 Carbon atoms have four valence electrons which allows carbon to bond
with multiple elements.
Macromolecules: Carbohydrates
 Living things use carbohydrates as their main source of energy. Plants, some
animals, and other organisms also use carbohydrates for structural
purposes.
 Carbohydrates are compounds made up of carbon, hydrogen, and
oxygen atoms.
Macromolecules: Lipids
 Lipids can be used to store energy. Some lipids are important parts of the
cell membranes which allows certain materials to enter or exit the cell.
 Lipids are made mostly from carbon and hydrogen atoms and are
generally do not dissolve in water.
 Steroids synthesized by the body are lipids as well. Many steroids, such as
hormones, serve as chemical messengers
Macromolecule: Nucleic Acid
 Nucleic acids store and transmit hereditary, or genetic, information.
 Nucleotides consist of three parts: a 5-carbon sugar, a phosphate group
and a nitrogenous base.
Macromolecule: Protein
 Proteins control the rate of reactions and regulate cell processes. Others
form important cellular structures, while still others transport substances into
or out of cells or help to fight disease.
 Amino acids are compounds with an amino group (–NH2) on one end and
a carboxyl group (–COOH) on the other end.
 Amino acids differ from each other in a side chain called the R-group,
which have a range of different properties.
Chemistry of Life
How do macromolecules effect living things?
Notes: Chemical Reaction and
Enzymes
 https://www.youtube.com/watch?v=XUn64HY5bug
Everything that happens in an
organism—its growth, its interaction
with the environment, its reproduction,
and even its movement—is based on
chemical reactions.
Chemical Reactions
 Chemical reactions involve changes in the chemical bonds that join atoms
in compounds.
 The elements or compounds that enter into a chemical reaction are known
as reactants.

The elements or compounds produced by a chemical reaction are known
as products.
Energy in Reaction
Energy is released or absorbed whenever
chemical bonds are formed or broken
during chemical reactions.
Activation Energy
The energy that is needed to get a
reaction started is called the activation
energy.
Catalyst
Enzymes act by lowering the activation energy
and speeding up chemical reactions.
Example: Digestion, cooking food deactivates
enzymes. Therefore your body has to work
internally to digest the food. Enzymes help with his
process!
Enzyme-Substrate Complex
 Enzymes provide a site where reactants(substrates) can
be brought together to react. The active site reduces
the energy needed for the reaction.
 The active site and the substrates have complementary
shapes.
Regulation of Enzyme Activity
 Temperature, pH, and regulatory molecules are all
factors that can affect the activity of enzymes.
Example: Enzymes produced by human cells generally
work best at temperatures close to 37°C.
The stomach enzyme pepsin, which begins protein
digestion, works best under acidic conditions.
Most enzymes are regulated by molecules that carry
chemical signals within cells, switching enzymes “on” or
“off” as needed.
Chemistry of Life
How do macromolecules effect living things?