Transcript Chapter 2.3: Carbon Compounds

Chapter 2.3:
Carbon Compounds
Chemistry is. . .
1. What life is made of
Example: Macromolecules
2. What life does
a.
b.
c.
d.
Growth
Reproduction
Movement
Interaction with the environment
Chemistry of Carbon
1. Carbon can form four covalent bonds.
2. Carbon can bond with carbon, hydrogen,
oxygen, nitrogen, phosphorus, and sulfur
6 protons
6 neutrons
6 electrons
first shell- 2
second shell- 4
Bonding Symbols
• A single bond is signified by a solid line
between symbols; shares 2 electrons
• A double bond is signified by two solid
lines between symbols; shares 4 electrons
• A triple bond is signified by three solid
lines between symbols; shares 6 electrons
Macromolecules
1. Macromolecules are
“Giant molecules”
2. Consist of monomers
(smaller units) that
join together to form
polymers.
a. This process is called
polymerization.
Macromolecules
•
Synthesizing covalent bonds between
the monomers involves losing a water
molecule- dehydration, or condensation
reaction
Macromolecules
•
Breaking the covalent bond within the
polymer to break off a monomer involves
breaking a water molecule and inserting
its pieces – hydrolysis
Types of macromolecules
1.
2.
3.
4.
Carbohydrates
Lipids
Nucleic Acids
Proteins
Carbohydrates
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1. Composition: made of C, H and O
atoms
*** monomer- monosaccharide
2.
Uses: Main source of energy for
organisms, structural purpose in cell
membrane, and exoskeleton of insects.
Carbohydrates
4. Examples
a. Sugars
1. Monosaccharide = single sugar molecule
2. Polysaccharide = polymer of monosaccharides
bonded together with a glycosidic linkage
Carbohydrates
4. Examples
b. Starch: Complex carbohydrates
(polysaccharides) that store extra sugar
1. In animals, starch is called glycogen, structural is
called chitin
2. In plants, “plant starch”, structural is called
cellulose
Lipids
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1.Composition: C, H, O atoms
*** subunits are glycerol and fatty acids
2.
Not soluble in water, hydrophobic
3.
Function: energy storage, main
part of cell membrane, hormones
4. Examples: fats, oils, waxes, steroids,
cholesterol
Lipids
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Types of fatty acids:
a.
Unsaturated fatty acids are found
in lipids that are liquid at room
temperature, C=C bonds
Example: Olive oil
b.
Saturated fatty acids are found in
lipids that are solids at room
temperature, no C=C bonds
Example: Shortening, butter
Types of Lipids
Saturated = only single bonds, maximum number of H atoms
Unsaturated = at least on C = C double bond
lipid
lipid
Glycerol + fatty acid
lipids + water
Proteins
1. Contain nitrogen, carbon, hydrogen,
oxygen
2. Uses:
1.
2.
3.
4.
5.
6.
Structure
Storage,
transport of other substances,
movement,
Immunity
Catalyze reactions (make them happen)
Proteins
1. Made of monomers called amino acids
a. 20 types of amino acids
b. Same general structure, but different R
group
We will draw the 4 levels of Protein structure on
the board…
Amino group
Carboxyl group
General structure
Alanine
Serine
Nucleic Acids
1. Contain hydrogen, oxygen, nitrogen,
carbon, phosphorus
2. Store and transmit genetic information
3. Two types
a. DNA (deoxyribonucleic acid)
b. RNA (ribonucleic acid)
Nucleotide
4. Made of monomers called nucleotides. A
nucleotide has three parts
a. 5-carbon sugar (ribose)
b. Phosphate group
c. Nitrogenous base
Carbon
Compounds
include
Carbohydrates
Lipids
Nucleic acids
Proteins
that consist of
that consist of
that consist of
that consist of
Glycerol and
Fatty acids
Nucleotides
Amino Acids
Monosaccharides
which contain
which contain
Carbon,
hydrogen,
oxygen
Carbon,
hydrogen,
oxygen
Sugars
and
starches
Fats,
oils,
waxes,
steroids
which contain
which contain
Carbon,hydrogen,
oxygen, nitrogen,
phosphorus
Carbon,
hydrogen,oxygen,
nitrogen
DNA or
RNA
Actin,
enzymes,
hemoglobin
Chapter 2.4:
Chemical Reactions and Enzymes
Chemical Reactions
Chemical Reaction: A change of one set
of chemicals into another
1. Can be slow or fast
2. Chemical reactions require collisions
between molecules
3. Involves changes in chemical bonds
A+BC+D
Chemical Reactions
1. Involves changes in chemical bonds
a. Reactants are elements or compounds that
enter into a chemical reaction.
Bonds of reactants are broken in a chemical
reaction.
b. Products are elements or compounds that
are produced in a chemical reaction.
Bonds of products are formed in a chemical
reaction
Chemical Reactions
1. Involves changes in chemical bonds
A+BC+D
Which are the reactants?
Which are the products?
Chemical Reaction Example:
CO2 in the body
1. Cells produce CO2,then blood carries
CO2 from cells to lungs (exhale)
Problem: CO2 is not soluble (dissolvable)
in water
Solution: A chemical reaction converts
CO2 to a soluble compound
In blood, CO2 converted to soluble compound:
CO2 + H2O → H2CO3
In the lungs, reaction is reverse to exhale CO2
H2CO3 → CO2 + H2O
Chemical reactions involve energy
1. Breaking and forming chemical bonds
requires energy release or absorption
2. Reactions that release energy can occur
spontaneously (but not all do)
a. Energy is released as heat
3. Reactions that absorb energy will not
occur without an energy source
4. What is activation energy? The energy
needed to get a reaction started
5. Some chemical reactions are really slow
or require lots of energy and cannot
occur on their own
Endergonic/ Endothermic
Energy-Absorbing Reaction
Exergonic/ Exothermic
Energy-Releasing Reaction
Activation
energy
Products
Activation energy
Reactants
Reactants
Products
Enzymes are catalysts.
1. A catalyst is a substance that speeds up the
rate of a chemical reaction by lowering the
activation energy of the reaction.
a. An enzyme is a protein that act as biological
catalyst
b. Enzymes speed up reactions that take place in
cells
Enzymes are catalysts.
c. Enzymes provides a site (called the active site)
where reactants can be brought together to react.
This decreases the activation energy
d. In a reaction involving an enzyme, the reactants
are called substrates
e. Enzymes can be reused, but can only have one
type of substrate
An enzymatic reaction:
Enzymes are catalysts.
f. The enzyme-substrate relationship is like that of a
“lock and key”
g. Enzymes can have an allosteric inhibitor in which
another molecule can turn the enzyme on or off by
binding to it (make the “lock” work or not)
http://www.execulink.com/~ekimmel/mixed_flash.htm
Enzymes are catalysts.
h. Enzymes can be affected by:
1. pH
2. Temperature
3. Other proteins
CO2 + H2O → H2CO3 requires
an enzyme called carbonic anhydrase
glucose + ATP → glucose-6-phosphate + ADP
Enzyme
(hexokinase)
Glucose
Substrates
Products
ADP
Glucose-6phosphate
Products
are released
ATP
Active site
Enzyme-substrate
complex
Substrates
are converted
into products
Substrates
bind to
enzyme