Download Chemistry in Biology

Cell Chemistry
Life depends on Chemistry
What does this mean?????
The Nature of Matter
What is the basic unit of matter?
Atoms!
Elements are made of like atoms.
Compounds are formed when two or
more elements combine.
Compound are held together by
bonds.
What is in our body????
How do we get these elements and
other compounds in our body?
How do we break them down?
Chapter 6
Chemistry in Biology
6.2 Chemical Reactions
 A chemical reaction is the
process by which atoms or
groups of atoms in substances
are reorganized into different
substances.
Chemical reaction
Physical reaction

How do we represent chemical reactions?
Chapter 6
Chemistry in Biology
6.2 Chemical Reactions
Chemical Equations
 Chemical formulas describe the substances in
the reaction and arrows indicate the process
of change.
 Reactants - starting substances
 Products - substances formed during the
reaction
Chapter 6
Chemistry in Biology
Example
 Glucose and oxygen react to form carbon
dioxide and water.
Chapter 6
Chemistry in Biology
6.2 Chemical Reactions
Balanced Equations
 Amazing
chemical reactions
Chemical reactions involve the breaking and
forming of bonds so they involve changes
of energy
Some reactions release energy and others
absorb energy.
Reactions that involve release energy are
often spontaneous
Reactions that absorb energy will not occur
without a source of energy
Remember matter and energy is
conserved
All living things require energy to
carry out chemical reactions.
Chapter 6
Chemistry in Biology
6.2 Chemical Reactions
Energy of Reactions
 The activation
energy is the
minimum amount of
energy needed for
reactants to form
products in a
chemical reaction.
Chapter 6
Chemistry in Biology
6.2 Chemical Reactions
 This reaction is
exothermic and
released heat energy.
 The energy of the
product is lower than
the energy of the
reactants.
Chapter 6
Chemistry in Biology
6.2 Chemical Reactions
 This reaction is
endothermic and
absorbs heat energy.
 The energy of the
products is higher
than the energy of
the reactants.
Chapter 6
Chemistry in Biology
6.2 Chemical Reactions
Enzymes
 A catalyst is a
substance that lowers
the activation energy
needed to start a
chemical reaction.
 Enzymes are an example of a biological
catalysts
 They help break down larger particles
that our body can use
 Let’s try it.
Chapter 6
Chemistry in Biology
6.2 Chemical Reactions
 The reactants that bind to the enzyme are called
substrates.
 The specific location where a substrate binds on
an enzyme is called the active site.
Chapter 6
Chemistry in Biology
6.2 Chemical Reactions
 The active site changes shape and forms
the enzyme-substrate complex
 Factors such as pH, temperature, and other
substances affect enzyme activity (rate)
Enzyme
*
enzyme
6-3 Objectives

Describe the importance of water to living systems

Compare the properties of acids and bases and their
role in living systems
Chapter 6
Chemistry in Biology
6.3 Water and Solutions
Acids and Bases
 Substances that release hydrogen ions (H+) when
dissolved in water are called acids.
 Substances that release hydroxide ions (OH–)
when dissolved in water are called bases.
Chapter 6
Chemistry in Biology
6.3 Water and Solutions
pH
 The measure of concentration of H+ in a
solution is called pH.
 Acidic solutions have pH values lower than 7.
 Basic solutions have pH values higher than 7.
Chapter 6
Chemistry in Biology
6.3 Water and Solutions
 Buffers are mixtures that can react with
acids or bases to keep the pH within a
particular range.
Chapter 6
Chemistry in Biology
6.4 The Building Blocks of Life
Organic Chemistry
 The element carbon
is a component of
almost all biological
molecules.
Chapter 6
Chemistry in Biology
6.4 The Building Blocks of Life
Macromolecules
 large molecules formed by joining smaller
organic molecules together.
 Polymers are molecules made from
repeating units of identical or nearly
identical compounds linked together by a
series of covalent bonds.
Chapter 6
Chemistry in Biology
6.4 The Building Blocks of Life
Carbohydrates
 Compounds composed of carbon, hydrogen, and
oxygen in a ratio of one oxygen and two
hydrogen atoms for each carbon atom (1:2:1)
Chapter 6
Chemistry in Biology
6.4 The Building Blocks of Life
Monomer or base unit
for sugar are
monosaccharides
Ex.
Glucose
Fructose
galactose
Disaccharide-
Two
monosaccharides
Examples
Sucrose

lactose
Polysaccharides
–
complex carbohydrates
Cellulose
Chitin
glycogen
 Functions
Quick
ENERGY
Energy
STORAGE in PLANTS
Energy
STORAGE in ANIMALS
Structural
SUPPORT
compounds for
Chapter 6
Chemistry in Biology
6.4 The Building Blocks of Life
Lipids
Molecules made mostly of
carbon and hydrogen
(a lot of!)
• Glycerol + 3 fatty acids
(Monomer)
 Fats with more than one double bond in
the tail are called polyunsaturated fats.
Functions
Long
of Lipids
term energy storage
Insulation
Sex hormones
Essential component of
cell membranes
steroids
 Examples
of lipids:
Waxes
Oils
Fats
Steroids
Chapter 6
Chemistry in Biology
6.4 The Building Blocks of Life
Proteins
 A compound made of small carbon
compounds called amino acids (monomer)
Held together with peptide bonds
 small compounds that are made of C, N,
O, and sometimes S.
 Only 20 amino acids in the world
 Large proteins are called polypeptides

hemoglobin
 Functions
of Proteins
 Support
 Movement
 Transport
 Defense
(immune sys)
 Metabolic
processes
 Coordination
and control
Chapter 6
Chemistry in Biology
6.4 The Building Blocks of Life
 Nucleic acids
 are complex macromolecules that store and
transmit genetic information.
 Nucleic acids are made of smaller repeating
subunits called nucleotides (monomer), composed
of N, O, H, P, and H atoms.
 Examples
DNA,
of nucleic acids
RNA, ATP
 Function
Carry
genetic information
ATP:
Energy molecule

https://www.youtube.com/watch?v=IJ7xOSCEmZw/