Transcript Chapter 3 Lecture

Biochemistry
Biology
Chapter 3
Garcia
3-1 Objectives
• Describe the structure of a water
molecule.
• Explain how water’s polar nature affects its
ability to dissolve substances.
• List two of water’s properties that result
from hydrogen bonding.
Polarity
polar compounduneven pattern of
charge
Hydrogen Bonding
attraction that holds two
water molecules
together
positive region is
attracted to negative
region
Cohesion & Adhesion
cohesion- attractive force between two
particles that are the same
adhesion- attractive force between two
unlike substances
capillarity- upward movement of water
molecules through narrow tubes
3-2 Objectives
• Define organic compound and name three
elements often found in organic
compounds.
• Explain why carbon forms so many
different compounds.
• Define functional group and explain its
significance.
• Compare a condensation reaction with
hyrdrolysis.
Organic Compounds
Substances that contain the element carbon.
May be bonded to other elements such as:
• hydrogen
• oxygen
• nitrogen
• other carbon atoms
Functional Group
clusters of atoms that
influence the
properties of the
molecule the
compose.
alcohol- organic
compound with a
hydroxyl group (-OH)
Large Carbon Molecules
monomer- simple
carbon molecules
polymer- repeated,
linked units of
monomers
Reactions
condensation rxn- monomers link to form
polymers
hydrolysis- breakdown of complex
molecules
ATP
adenosine triphosphatecompound that
contains a large
amount of energy
3-3 Objectives
• Define monosaccharide, disaccharide, and
polysaccharide, and discuss their
significance to organisms.
• Compare the structures of the various
types of proteins.
• Relate the structure of lipids to their
functions.
• List two essential functions of nucleic
acids.
Classes of Organic Compounds
1.
2.
3.
4.
carbohydrates
lipids
proteins
nucleic acids
Carbohydrates
compounds composed
of carbon, hydrogen
and oxygen in a ratio
of 2 hydrogen atoms
to 1 oxygen atom
Carbohydrates
monosaccharide- monomer of a
carbohydrate
disaccharide- a double sugar formed from a
condensation rxn of two monosaccharides
polysaccharide- molecule composed of
three or more monosaccharides
Proteins
organic compounds composed mainly of carbon,
hydrogen, oxygen and nitrogen
Amino Acids
monomer building blocks of proteins
20 different types
Dipeptides and Polypeptides
dipeptide- two amino acids sharing a covalent
bond as a result of a condensation rxn
polypeptide- long chain of amino acids
Enzymes
organic molecules that
act as catalysts
most are proteins
substrate- reactant
being catalyzed
Lipids
large, nonpolar molecules that do not
dissolve in water
higher ratio of carbon and hydrogen atoms
to oxygen atoms than carbohydrates
store energy efficiently
Fatty Acids
unbranched carbon chains that mke up most
lipids
contains a long straight carbon chain with a
carboxyl group (-COOH) attached at one
end
hydrophilic- water loving
hydrophobic- water fearing
Classes of Lipids
triglyceride- composed of three molecules of
fatty acid joined to one molecule of
alcohol glycerol
phospholipids- have two fatty acids joind by
a molecule of glycerol
wax- long fatty-acid chain joind to a long
alcohol change
Steroid
a lipid composed of four fused carbon rings
with various functional groups attached to
them
many hormones are steroid compounds i.e.
cholesterol or testosterone
Nucleic Acids
large, complex organic molecules that store
information
ribonucleic acid (RNA)- stores and transfers
information for making proteins
nucleotides- linked monomers that make up
DNA and RNA