Macromolecules
SC.912.L.18.1
Describe the basic
molecular structures
and primary
functions of the four
major categories of
biological
macromolecules.
Source: http://biologypatriciam.blogspot.com
What do I need to know?
 identify and/or describe the basic
molecular structure of carbohydrates,
lipids, proteins, and/or nucleic acids
 describe the primary functions of
carbohydrates, lipids, proteins, and/or
nucleic acids in organisms
 explain how enzymes speed up the
rate of a biochemical reaction by
lowering the reaction’s activation
energy
 identify and/or describe the effect of
environmental factors (concentration,
pH, and temperature)on enzyme
activity
Molecules of Life
What are bodies mostly
made of?
 Carbon molecules
 carbohydrates
(sugars & starches)
 proteins
 fats (lipids)
 nucleic acids (DNA,
RNA)
Carbon’s Bonding Properties
 carbon forms
covalent bonds with
up to four other
atoms, including
other carbon atoms
 many carbon-based
molecules are made
of many small
subunits bonded
together
Structure of Carbohydrates
 contain carbon,
hydrogen and
oxygen in the
ratio 1:2:1
Function of Carbohydrates
 include sugars and
starches
 can be broken down
to provide energy for
cells
 some are part of cell
structure
Structure of Lipids
 are non-polar molecules
that include fats, oils,
and cholesterol
 many contain carbon
chains called fatty acids
 fats and oils contain fatty
acids bonded to glycerol
 contain carbon,
hydrogen and oxygen
Function of Lipids
 are a great source of
stored energy so we
have it in the future
 make up cell membranes
 insulate the body to
maintain normal body
temperature and they
cushion the internal
organs for protection
 produce hormones for
the body called steroids
 waterproof surfaces of
animals, plants, and
fruits- (these are waxes)
Structure of Proteins
 are polymers of amino
acid monomers
 each protein is made up
of Carbon, Hydrogen,
Oxygen, and Nitrogen
The shapes of proteins are
like a balled up piece of
string
Amino
Acid
chain
All
wound
up
Function of Proteins
 major structural molecules in
living things for growth and
repair : muscles, ligaments,
tendons, bones, hair, skin,
nail
 found in all cell membranes
 make up antibodies in the
immune system
 make up enzymes for helping
chemical reactions
 make up non-steroid
hormones which regulate
bodily functions
Structure of Nucleic Acids
 polymers of
monomers called
nucleotides
 nucleotides are
made of a sugar,
phosphate group,
and a nitrogen base
A phosphate group
deoxyribose (sugar)
nitrogen-containing
molecule,
called a base
Function of Nucleic Acids
 DNA stores genetic information
DNA
 RNA builds proteins
RNA
The Molecules of Life
 Create a foldable booklet (see
below).
 As you watch the video draw the
structure and list the
characteristics of carbohydrates,
lipids, proteins, and nucleic
acids under the appropriate tabs.
Video: https://www.youtube.com/watch?v=QWf2jcznLsY
Enzymes
 type of protein that act
as biological catalysts,
speeding up chemical
reactions without being
used up
 work at optimum
temperatures and pH
 they are specific – Lock
and Key Model
Effects of Environmental Factors
on Reaction Rate
Environmental Factors
 concentration
 pH
 temperature
Lab: Enzyme Catalysis
 Enzymes catalyze
reactions by lowering
the activation energy
necessary for a
reaction to occur.
 In this laboratory, you
will study some of the
basic principles of
molecular movement in
solution and perform a
series of activities to
investigate these
processes.
Show What You Know
As food travels through the digestive system, it is
exposed to a variety of pH levels. The stomach
has a pH of 2 due to the presence of hydrochloric
acid (HCl), and the small intestine has a pH
ranging from 7 to 9. HCl converts pepsinogen
into pepsin, an enzyme that digests proteins in
the stomach. Which of the following most likely
happens to pepsin as it enters the small
intestine?
A. It becomes inactive.
B. It begins to replicate.
C. Its shape changes to engulf large proteins.
D. Its activity increases to digest more proteins.
Show What You Know
Which of the following best compares the
structures of lipids and carbohydrates?
A. Both are made up of monosaccharide
monomers, but lipids are hydrophobic and
carbohydrates are hydrophilic.
B. Both consist of carbon, hydrogen, and
oxygen, but carbohydrates have repeating
structural units and lipids do not.
C. Both contain carbon and hydrogen, but
carbohydrates also contain oxygen and lipid
contain nitrogen.
D. Both have a carbon backbone, but lipids
also have an amino group and
carbohydrates have a carboxylic acid group.
Show What You Know
Which of the following best describes the difference
between the functions of nucleic acids and enzymes?
A. Nucleic acids are used as the building block of
proteins, while enzymes are used as the building
blocks of phospholipids.
B. Nucleic acids contain the genetic code for protein
synthesis, while enzymes catalyze chemical
reactions.
C. Nucleic acids inhibit biochemical reactions, while
enzymes provide structural support in cells.
D. Nucleic acids transmit signals that begin
biochemical processes, while enzymes convert
carbohydrates into lipids and proteins.
Show What You Know
Some proteins catalyze biochemical
reactions. If a genetic defect prevented a
protein catalyst from being produced, which
of the following do you predict would happen
in the cell?
A. The cell would find a different type of
protein to catalyze the reaction.
B. The reaction the protein catalyzes would
proceed very slowly or not all.
C. The reaction the protein catalyzes would
only occur in some places in the cell.
D. The reverse reaction of the one the protein
catalyzes would begin to proceed.