Introductory Biochemistry PowerPoint

The basic building blocks of life
Basic Chemistry
Atoms: the most basic unit of matter (that
still has the characteristics of that
element) {12}
Subatomic Particles (make up atoms) {7}
a. protons (+)
b. electrons (-)
c. neutrons (none)
Basic Chemistry Continued
3. Elements: A group of all one kind of atom
(like a sheet of Aluminum foil). Elements
cannot be broken down any further.
4. Compound: a molecule made with 2 or
more elements joined chemically (more
later). {13}
5. Molecule: the smallest unit of a compound
that maintains its characteristics (must be
neutral - no charge).
Atom Structure
Protons and neutrons
compose the nucleus
of an atom (located in
the center).
The positive charge of
the nucleus is
balanced by a cloud
of negative electrons
that orbit the nucleus.
Electrons orbit in specific “energy levels”
-1st energy level holds 2 electrons
-2nd – holds 8
-3rd – 18 … (and so on for bigger and bigger
Atomic #
The Periodic Table {1 - 6}
Atomic Mass
# = the number of protons in
the nucleus of an atom.
 ATOMIC MASS = the mass of the
atom which is just protons + neutrons
(electrons have very very little mass).
*Measured in AMUs = atomic mass
units which is equal to the weight of 1
proton or one neutron (p & n weigh
the same). {8, 9}
So where are we now?
How many of each are there in the following
compounds? {15, 16, 20}
a. Elements
3 atoms, 2 elements
b. Atoms
3 atoms, 2 elements
54 atoms, 3 elements
# of molecules
6 atoms, 3 elements
24 atoms, 3 elements
So how do all of those elements come
together to form molecules/compounds?
Answer? BONDING!
Covalent Bonding – Atoms share electrons in
their outer shells to become stable. {17}
Ex: Water (H20), Glucose (C6H1206), Carbon Dioxide (CO2)…
Ionic Bonding – Sometimes atoms lose or gain
electrons giving them + or – charges or IONS
{11}. Charged particles are “unhappy” and want
to combine to make a neutral compound. When
this occurs an IONIC BOND forms! {18}
Ex : Salt (NaCl) Na = (+) and Cl = (-)
When reactions take place to form compounds they are
represented by chemical equations. Equations must be
balanced on both sides (same number of each atom on
opposite sides of the equation)
Na + Cl
Look Familiar?
2H + O
6H2O + 6CO2
C6H12O6 + 6O2
Can you balance this one?
3 2
+ __O
2 2 O3
What’s missing?
What are some special compounds
that exist in nature?
 Bases
 Carbohydrates
 Proteins (Enzymes)
 Fats/Lipids
 Nucleic acids
All of these are
organic (Carbon)
compounds that
are vital in ALL
living things!
Water molecules tend to break
apart occasionally (H20  H+
and OH-) *But these # H+/OH- in
the H2O solution are balanced*
When other substances
containing H+ or OH- are
dissolved in water the
concentration of either H+ or OHchanges (like adding HCL gas to
If the concentration of H+ ions in
the solution are greater than the
concentration of OH- ions then
the solution is an acid
If the concentration of OH- ions
in the solutions are greater than
the concentration of H+ ions then
the solution is a base
Organic Compounds:
1)Carbohydrates {21}
Composed of C,H, & O
Ratio of 2 H atoms to each O atom
Sugars and Starches – energy sources for life
Monosaccharides (simple sugars)
-Ex :C6H12O6 (glucose)
Disaccharides = 2 monosaccharides
-Ex : sucrose (table sugar) and lactose
Polysaccharides = starches
2) Lipids/Fats {22}
Also contain C, H, & O
# of H atoms per molecule MUCH greater than # O
atoms (Ex: C57H11006)
Stored energy (food scarcity) and also used in cell
Made of Glycerols and Fatty Acids
3) Proteins {23}
Composed of C, H, & O, but also N
Many different kinds of proteins with many different jobs (Ex:
building living material, carrying out reactions, fighting disease…)
Made of chains of simple compounds called AMINO ACIDS (20
AA bonded = peptide, multiple AA’s bonded = polypeptide (change
order – different proteins)
Special proteins – ENZYMES speed up biological reactions
An antibody
pictures of
Enzymes {25}
Organic (means they can denature)
 Specific to a substrate (only work on one
thing – thus there are lots and lots of
 They work to speed up chemical reactions
 They are recyclable (not used in the
Enzyme vs Catalyst {24}
A catalyst is anything that speeds up a
chemical reaction
 An enzyme is an organic catalyst
 So…an enzyme is always a catalyst, but a
catalyst is not always an enzyme!
4) Nucleic Acids {29!}
The organic molecules
that form a CODE that
control an organisms’
appearance and
deoxyribonucleic acid
= genetic info
RNA – ribonucleic
acid = messenger that
carries info for DNA
ATP – Energy
PS - C,H,O,N
Remember! All four of these organic
compounds are made out of the CHON…
 Hydrogen
 Oxygen
 Nitrogen
 Phosphorus and Sulfur are common too.
 All living things are made from the CHON!!!!!!!