Transcript Ch.2 Chemistry of Life

Chemistry of Life
Imagine this..
It has been a long day of school, and
you are extremely frustrated because all
of your teachers, except you’re
wonderful Biology teacher, have
assigned you tons of homework. “I’m
gonna have to pull an all-nighter,” you
think.
Imagine this..
You’re parents decides to make you
dinner to help you get through the
night. What should they cook?
Concept Map
Chemistry
Atoms and Chemical
Bonding
Water and it’s
Properties
Carbon Compounds
Concept Map
Atoms and
Chemical
Bonding
History
Structure of the
Atom
Protons, Neutrons,
And electrons
Chemical
Bonding
Ionic Bonds
Covalent
Bonds
Hydrogen
Bonds
Concept Map
Water and
It’s Properties
Cohesion
Adhesion
Acids and Bases
Concept Map
Carbon
Compounds
include
Carbohydrates
Lipids
Nucleic acids
Proteins
that consist of
that consist of
that consist of
that consist of
Sugars and
starches
Fats and oils
Nucleotides
Amino Acids
which contain
which contain
Carbon,
hydrogen,
oxygen
Carbon,
hydrogen,
oxygen
which contain
which contain
Carbon,hydrogen,
oxygen, nitrogen,
phosphorus
Carbon,
hydrogen,oxygen,
nitrogen,
Why do we learn Chemistry in Biology?
Chemistry is the study of the
composition and properties of Matter.
Chemistry is related to Biology because
all organisms are composed of chemical
substances.
Ch. 2. Outline
2-1: Nature of Matter
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Atoms
Elements and Isotopes
Chemical Compounds
Chemical Bonds
2-2: Properties of Matter
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Water Molecule
Solutions and Suspensions
Acids, Bases, and pH
Ch. 2. Outline
2-3: Carbon Compounds
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Macromolecules
Carbohydrates
Lipids
Nucleic Acids
Proteins
2-4: Chemical Reactions and Enzymes
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Chemical Reactions
Energy in Reactions
Enzymes
Enzyme Action
Section 1: Nature of Matter
What are Atoms?
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The smallest unit of matter that cannot be broken
down chemically
What composes Atoms?
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Protons – positively charged (p+) particles, found
in the nucleus
Neutrons – Particles with no charge (n0), found in
the nucleus
Electrons – negatively charged (e-), found in
energy levels
History of the Atom
Democritus – “Atomos
Thomson Plum Pudding – “Plum
pudding Model
Rutherford model – Planetary
structure
Bohr Model – Discrete orbitals
Electron Cloud Model – Electrons orbit
with specific clouds and shapes.
The Atom
Nature of Matter (con’t)
What are elements?
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An element is a pure substance made up of
only one kind of atom, represented by
symbols, such as, H, O, N, C, etc.
What is an isotope?
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Isotopes are atoms of an element that
contain different numbers of neutrons
 Carbon-12, Carbon-13, and Carbon-14
Chemical Bonding
Chemical Bonding describes the forces which
joins atoms to form compounds.
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A compound is a substance formed by the
chemical combination of two or more elements in
definite proportions
There are three types of bonds that you will
learn about:
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Covalent Bonds
Ionic Bonds
Van der Waals Forces
Chemical Bonding (con’t)
When do covalent bonds form?
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Covalent bonds form when two or more
atoms share electrons.
A molecule is a group of atoms held
together by covalent bonds
What is a polar molecule?
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A polar molecule has an unequal
distribution of charge
 I.e. H2O acts like a charge particle.
Covalent Bonds
Chemical bonding (con’t)
Van der Waals force or Hydrogen
Bonding is a weak chemical attraction
between polar molecules
Chemical Bonding (con’t)
What is an Ion?
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An atom or molecule that has gained or
loss one or more electrons.
How is an Ionic Bond formed?
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When two or more ions of opposite charge
are held together
Ionic Bonds
Sodium atom (Na)
Chlorine atom (Cl)
Sodium ion (Na+)
Chloride ion (Cl-)
Transfer
of electron
Protons +11
Electrons -11
Charge
0
Protons +17
Electrons -17
Charge
0
Protons +11
Electrons -10
Charge
+1
Protons +17
Electrons -18
Charge
-1
Ionic Bonds
Water and Living Things
About 70% of our body is water, both
inside and outside of all of our cells.
There are four major properties of
water in biology:
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Storage of Heat
Cohesion
Surface Tension
Adhesion
Properties of Water
Storage of Heat – Water helps cells maintain
homeostasis by controlling internal body temperature
because it retains heat
Cohesion – An attraction between substances of the
same kind, I.e. water to form drops
Surface tension – forms drops of water because of
attraction, prevents surface from breaking easily
Adhesion – an action between different substances,
I.e water to walls of plant tube to cause capillary
action.
Solutions and Suspensions
Water is not always pure—it is often
found as part of a mixture
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Mixture – a material composed of two or
more elements that are physically
combined not chemically combined.
Example: The Atmosphere, Your body,
Water.
Solution and Suspensions
A solution is when a chemical change occurs
that breaks apart bonds, usually in water.
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Salt and Water
Two parts of a solution
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Solute – the substance that is dissolved
Solvent – the substance that does the dissolving
Water is an excellent solvent because of it’s
polar bonds.
Aqueous Solutions
An aqueous solution is a mixture in
which one or more substances are
distributed evenly in water or blood to
be delivered in the body
There are two main properties of
solution:
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Polarity
pH
Properties of Solutions
Polarity – Water is the universal solvent
due to the fact that it is a polar
substance. The polarity of water helps
break apart bonds, especially ionic
bonds. Nonpolar molecules, such as
those found in oils, do not “mix” or
dissolve in water.
Polarity of Water
Properties of Solutions (con’t)
The Acidity of solutions is a very important property
in biology.
Acidity is measured using the pH scale
 pH measure the amount of H+ ions in a solution
 What would pOH measure?
Acids are solutions that range from 0 to 7 on the pH
scale. They form hydrogren ions when dissolved in
water
Bases are solutions that range from 7 to 14 on the
pH scale. They form hydroxide ions when dissolved
in water.
pH Scale
What are some acids and bases found in your body?
Section 3: Chemistry of Cells
As we go further into Biology, we will
learn about cells and cell functions. An
important aspect of biological cells are
Carbon Compounds.
Carbon Compounds are made up of
building blocks called Monomers.
Many monomers together are called a
polymer
Carbon Compounds
There are 4 main organic compounds
found in the body:
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Carbohydrates
Lipids
Protein
Nucleic Acids
Name an example of each.
Carbon Compounds (con’t)
Carbohydrates
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Contains C,H, O with a 1:2:1 ratio.
Quick Source of energy, “carbo loading”
Basic monomers are monosaccharides
 Glucose, Fructose, Galactose, etc.
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Two monosaccharides form a disaccharide
 Sucrose, more commonly known as Table Sugar
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Many monosaccharides come together and make
Polysaccharides
 Starch – plants
 Glycogen – animals
 Cellulose in plants’ cell walls
Carbohydrates
Carbon Compounds (con’t)
Lipids
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Also contains C, H, O, in no specific ratio
Include fats, oils, waxes, and steroids
Important in the structure and function of
cell membrane, and light absorbing
compounds called pigments
A long-term store for energy
Monomers are one glycerol and three fatty
acids, called a triglyceride
Carbon Compounds (con’t)
Saturated fats: all the C atoms
in the fatty acids are bonded to
two Hydrogen atoms forming a
straight chain.
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Will they be solid or liquid at
Room Temperature?
Unsaturated fats: some of the
C atoms are linked by a double
covalent bond with only one
hydrogen atoms which forms
kinks in the chain.
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Will they be solid or liquid at
Room Temperature?
Carbon Compounds (con’t)
Proteins
 Large macromolecules formed from monomers called amino
acids
 Generally fold into compact shapes on interaction with water
 Many important functions in the body:
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Collagen
Hemoglobin
Antibodies – aid immune system
Actin & Myosin
Enzymes – catalysts that speed up chemical reactions by
lowering activation energy
Hemoglobin and Actin/Myosin Complex
Activation Energy
Energy-Absorbing Reaction
Energy-Releasing Reaction
Activation
energy
Products
Activation energy
Reactants
Reactants
Products
Enzyme and Substrate
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
Carbon Compounds
Nucleic Acids
 Found in every cell
 Made up of monomers called Nucleotides
 DNA
 Deoxyribonucleic Acid
 RNA
 Ribonucleic Acid
 ATP
 Adenosine Triphosphate
 A high-energy storing molecule recycled in cells
DNA Structure
End of Organic Compounds