Chemistry Basics
1
Compounds
Most elements
do not exist
by
themselves
Readily
combine with
other
elements in a
predictable
fashion
2
A compound is a pure
substance made up of
atoms of two or more
elements
The proportion of atoms
are always fixed
Chemical formula shows the
kind and proportion of
atoms of each element
that occurs in a particular
compound
3
Molecules are the
simplest part of a
substance that
retains all of the
properties of the
substance and
exists in a free
state
Some molecules are
large and complex
4
Energy and Chemical Reactions
Living things
undergo
thousands of
chemical
reactions as part
of the life
process
5
Many are very complex involving multi-step
sequences called biochemical pathways
Chemical equations represent chemical reactions
Reactants are shown on the left side of the
equation
Products are shown on the right side
6
Macromolecule Equations: Reactants and Products
____________________:
sunlight
6CO2
+ 6H2O
 C6H12O6 +
6O2
______ + _______
_______ + _________
_____________________:
C6H12O6
+ 6O2  6CO2 + 6H2O + ATP
______ + _______
_____ + ______ + _____
7
Photosynthesis 6CO2
+
sunlight
6H2O

C6H12O6 +
6O2
The process used by plants, algae, and some bacteria
to create sugar (energy) from sunlight
8
Cellular Respiration
The process used in the cells mitochondria to create
energy from sugar
C6H12O6
+
6O2
 6CO2
+ 6H2O + ATP
9
ATP - ENERGY
What is ATP?
Energy used by all Cells
Adenosine Triphosphate
Organic molecule containing high-energy Phosphate
bonds
What Does ATP Do for You?
It supplies YOU with
ENERGY!
10
ATP structure
11
Enzymes are an important class of catalysts in
living organisms
Mostly protein
Thousands of different kinds
Each specific for a different chemical
reaction
12
Enzyme Structure
Enzymes work on
substances called
substrates
Substrates must fit into a
place on an enzyme
called the active site
Enzymes are reusable!
13
Solutions
A solution is a
mixture in
which 2 or more
substances are
uniformly
distributed in
another
substance
14
Solute is the
substance
dissolved in the
solution
Particles may be
ions, atoms, or
molecules
Solvent is the
substance in which
the solute is
dissolved
Water is the
universal solvent
15
Biochemistry of Cells
16
Organic vs. Inorganic Molecules
Organic Molecules or Compounds:
Living things
ALL organic molecules contain the element CARBON!!!
Anything that is considered “biotic”
Examples:
Inorganic Molecules or Compounds:
All non-living or never were living things
Anything that is considered “abiotic”
Examples:
17
Uses of Organic Molecules
Americans consume
an average of 140
pounds of sugar
per person per
year
Cellulose, found in
plant cell walls, is
the most abundant
organic compound on
Earth
18
Uses of Organic Molecules
A typical cell in
your body has
about 2 meters
of DNA
A typical cow
produces over
200 pounds of
methane gas
each year
19
Water
About 60-90 percent
of an organism is
water
Water is used in
most reactions in
the body
Water is called
the universal
solvent
20
Water Properties
Polarity
A molecule with positive and
negative charged ends has
polarity and is called a polar
molecule.
The water molecule’s polarity
allows it to bond with
adjacent water molecules.
The positively charged
hydrogen end of one water
molecule attracts the
negatively charged oxygen
end of
another water molecule.This
bond between water
molecules is
called a hydrogen bond.
21
Water Properties
Cohesiveness
Adhesiveness
Cohesion/Adhesion. Because hydrogen bonds
attract water molecules to each other, they tend
to stick together. This is cohesion. Water also
sticks to other materials due to its polar nature.
This is adhesion.
22
Surface
Tension
A skin-like surface
formed due to
the polar nature of
water. Surface
tension is water’s
resistance to
objects attempting
to penetrate its
surface.
23
Water Properties
Surface
Tension
24
Draw and label a molecule of water:
25
Giant Molecules - Polymers
Large molecules
are called polymers
Polymers are built
from smaller
molecules called
monomers
Biologists call
them
macromolecules
26
Examples of Polymers
Proteins
Lipids
Carbohydrates
Nucleic Acids
27
Most Macromolecules are Polymers
Polymers are made by stringing together
many smaller molecules called monomers
Nucleic Acid
Monomer
28
Linking Monomers
Cells link monomers by a process
called dehydration synthesis
(removing a molecule of water)
Remove
H
H2O Forms
Remove OH
This process joins two sugar monomers
to make a double sugar
29
Breaking Down Polymers
Cells break down
macromolecules
by a process
called
hydrolysis
(adding a
molecule of
water)
Water added to split a double sugar
30
Macromolecules in Organisms
There are four categories of large
molecules in cells:
Carbohydrates
Lipids
Proteins
Nucleic Acids
31
Carbohydrates
Carbohydrates include:
Small sugar molecules
in soft drinks
Long starch molecules
in pasta and potatoes
32
Monosaccharides:
Called simple sugars
Include glucose,
fructose, & galactose
Have the same
chemical, but
different structural
formulas
C6H12O6
33
Monosaccharides
Glucose is found in
sports drinks
Fructose is found
in fruits
Honey contains
both glucose &
fructose
Galactose is called
“milk sugar”
34
Isomers
Glucose &
fructose are
isomers
because
they’re
structures are
different, but
their chemical
formulas are
the same
35
Cellular Fuel
Monosaccharides
are the main
fuel that cells
use for cellular
work
36
Disaccharides
A disaccharide is a
double sugar
They’re made by
joining two
monosaccharides
Involves removing
a water molecule
(dehydration)
37
Disaccharides
Common disaccharides include:
Sucrose (table sugar)
Lactose (Milk Sugar)
Maltose (Grain sugar)
38
Disaccharides
Sucrose is composed
of glucose + fructose
Maltose is
composed of 2
glucose molecules
Lactose is made
of galactose +
glucose
GLUCOSE
39
Polysaccharides
Complex
carbohydrates
Composed of many
sugar monomers
linked together
Polymers of
monosaccharide
chains
40
Starch
Starch is an example of a
polysaccharide in plants
Plant cells store starch
for energy
Potatoes and grains are
major sources of starch
in the human diet
41
Glycogen
Glycogen is an example
of a polysaccharide
in animals
Animals store excess
sugar in the form of
glycogen
Glycogen is similar in
structure to starch
42
Cellulose
Cellulose is the most abundant organic
compound on Earth
It forms cable-like fibrils in the
tough walls that enclose plants
It is a major component of
wood
It is also known as dietary fiber
43
Dietary Cellulose
Most animals cannot derive nutrition
from fiber
They have
bacteria in
their digestive
tracts that can
break down
cellulose
44
Sugars in Water
Simple sugars and double sugars dissolve
readily in water
They are
hydrophilic,
or “waterloving”
45
Lipids
Lipids are hydrophobic –”water fearing”
Do NOT mix with water
Includes
fats,
waxes,
steroids,
& oils
46
Function of Lipids
Fats store energy, help to insulate the
body, and cushion and protect organs
47
Types of Fatty Acids
Unsaturated fatty acids have less than
the maximum number of hydrogens
bonded to the carbons (a double bond
between carbons)
Saturated fatty acids have the
maximum number of hydrogens bonded
to the carbons (all single bonds
between carbons)
48
Triglyceride
Monomer of lipids
Composed of
Glycerol & 3
fatty acid chains
Glycerol forms
the “backbone”
of the fat
49
Fats in Organisms
Most animal fats have a high proportion
of saturated fatty acids & exist as
solids at room temperature (butter,
margarine, shortening)
50
Fats in Organisms
Most plant oils tend to be low in
saturated fatty acids & exist as
liquids at room temperature (oils)
51
Fats
Dietary fat consists largely of the
molecule triglyceride composed of
glycerol and three fatty acid chains
52
Steroids
The carbon skeleton
of steroids is bent
to form 4 fused
rings
Cholesterol is
the “base
steroid” from
which your body
produces other
steroids
Estrogen & testosterone are also steroids
53
Proteins
Proteins are polymers made of
monomers called amino acids
All proteins are made of 20 different
amino acids linked in different orders
Proteins are used to build cells, act
as hormones & enzymes, and do much
of the work in a cell
54
Four Types of Proteins
Storage
Structural
Contractile
Transport
55
Linking Amino Acids
Cells link amino
acids together to
make proteins
The process is
called dehydration
synthesis
Peptide bonds
form to hold the
amino acids
together
56
Proteins as Enzymes
Many proteins act as biological catalysts
or enzymes
Thousands of different enzymes exist
in the body
Enzymes control the rate of chemical
reactions by weakening bonds, thus
lowering the amount of activation
energy needed for the reaction
57
Enzymes
Enzymes are globular proteins.
Their folded conformation
creates an area known as the
active site.
The nature and arrangement of
amino acids in the active site
make it specific for only one
type of substrate.
58
Enzyme + Substrate = Product
59
How the Enzyme Works
Enzymes are reusable!!!
60
Nucleic Acids
Store hereditary information
Contain information for making all
the body’s proteins
Two types exist --- DNA &
RNA
61
Nucleic Acids
Nucleic
acids are
polymers of
nucleotides
62
Bases
Each DNA
nucleotide has one
of the following
bases:
–Adenine (A)
Thymine (T)
Cytosine (C)
–Guanine (G)
–Thymine (T)
–Cytosine (C)
Adenine (A)
Guanine (G)
63
Nucleotide Monomers
Form long chains
called DNA
Nucleotides are
joined by sugars
& phosphates on
the side
64
DNA
Two strands of
DNA join
together to form
a double helix
65
RNA – Ribonucleic Acid
Nitrogenous base
(A,G,C, or U)
Ribose sugar
has an extra
–OH or
hydroxyl
group
It has the
base uracil (U)
instead of
thymine (T)
Uracil
Phosphate
group
Sugar (ribose)
66
Nucleic Acids
67
Summary of Key Concepts
68
Macromolecules
69
Macromolecules
70
End
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