1. Patterns of Chemical Reactions and Biochemistry
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Chapter 2 : Pages 37-42
Patterns of Chemical Reactions and Biochemistry

2. 3 Types of Chemical Reactions
© 2015 Pearson Education, Inc.
3 Types of Chemical Reactions
Synthesis: something is built
Requires energy; smaller to bigger
Ex.: protein synthesis; monosaccharides to polysaccharides
Decomposition: something is broken down
Energy is released; bigger to smaller
Ex.: polysaccharide to monosaccharide;
Exchange: rearrangement of molecules

3. Figure 2.10a Patterns of chemical reactions.
(a) Synthesis reactions
Smaller particles are
bonded together to form
larger, more complex
molecules.
Example
Amino acids are joined
together to form a protein
molecule.
Amino acid
molecules
Protein
molecule

4. Figure 2.10b Patterns of chemical reactions.
(b) Decomposition reactions
Bonds are broken in larger
molecules, resulting in
smaller, less complex
molecules.
Example
Glycogen is broken down to
release glucose units.
Glycogen
Glucose
molecules

5. Figure 2.10c Patterns of chemical reactions.
(c) Exchange reactions
Bonds are both made
and broken.
Example
ATP transfers its terminal phosphate
group to glucose to form glucose-
phosphate. P P P
Glucose
Adenosine triphosphate
(ATP) P P P
Glucose-
phosphate
Adenosine diphosphate
(ADP)

6. Patterns of Chemical Reactions
© 2015 Pearson Education, Inc.
Patterns of Chemical Reactions
Many physiological chemical reactions are reversible
Four main factors influence rate of rx:
Temperature
Concentration
Particle size
Presence of catalyst/enzyme

7. Biochemistry: Essentials for Life
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Biochemistry: Essentials for Life
Inorganic compounds: (Lack carbon)
small, simple molecules
Include water, salts, and some acids and bases
Organic compounds (MACROmolecules)
Contain carbon
Include:
carbohydrates, lipids, proteins, and nucleic acids

8. Water and Chemical reactions
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Water and Chemical reactions
Water
Most abundant inorganic compound in the body
It cushions- protects brain, developing fetus…
important reactant in some chemical reactions:
hydrolysis reactions
dehydration synthesis

9. Hydrolysis Reaction: reactions that require water
(b) Hydrolysis
Monomers are released by the addition of a water molecule,
adding OH to one monomer and H to the other.
H2O
Monomer 1
Monomer 2
Monomers linked by covalent bond
water is ADDED to the reaction so molecular bonds can be broken

10. Dehydration Synthesis: reactions that remove water
Figure 2.13a Dehydration synthesis and hydrolysis of biological molecules.
Dehydration Synthesis: reactions that remove water
(a) Dehydration synthesis
Monomers are joined by removal of OH from one monomer
and removal of H from the other at the site of bond formation.
H2O
Monomer 1
Monomer 2
Monomers linked by covalent bond
smaller molecules are joined to form larger molecules through the removal of water molecules

11. Important Inorganic Compounds
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Important Inorganic Compounds
Salts
Easily dissociate (break apart) into ions in the presence of water
Vital to many body functions
Examples include Chlorides, Phosphates, Fluorides, Sulphates, Carbonates
of Sodium, Potassium, Magnesium, Ammonium, Calcium
Used in nerve impulse, bones, teeth, muscle contraction, pH balance

12. Acids, Bases, and buffers
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Acids, Bases, and buffers
Acids (pH less than 7)
Bases (pH greater than 7)
Buffers—chemicals that can regulate pH change
Our bodies contain natural buffers that keep pH constant to maintain homeostasis
The kidneys and lungs regulate pH through filtration/excretion and respiration (respectively)