Transcript Chemistry for Anatomy and Physiology

Chemistry for Anatomy and
Physiology
Matter
• Can be seen, smelled or felt
• Occupies space and has mass (weight)
• We look at how building blocks are put
together
Energy
• The ability to do work
• Massless; measured by its effect on matter
Types of Energy
• Chemical
• Electrical
• Mechanical
• Radiant
Chemical Energy
Stored in atomic bonds
Released when bonds
are broken
Electrical Energy
• Movement of charged
particles
• Electrons along a wire
at home
• Charged particles
across a membrane
in your body
Mechanical Energy
• Running, Riding a
bike, paddling a
canoe…
• Muscle contraction
moves the bones of
your body
Radiant Energy
• Travels in waves
• Electromagnetic Spectrum
• Includes x-rays, infrared, visible light, radio and
Ultraviolet
• Important in vision and Vitamin D synthesis
Can we convert from one type to
another???
• While it is never
created or destroyed,
some energy is lost
as heat.
• Example= Eating,
only 10% of the
energy is retained
and the rest is lost as
heat.
Path of Energy
• Begins as sun
energy
• Photosynthesis
converts sun
energy to chemical
• We eat plants and
absorb the
nutrients
Food to Macromolecules
• When we eat,
chemical reactions
produce heat
• Keeps our body
temperature stable
• Provides building
blocks for
macromolecules
Energy Storage
• Energy is stored in
ATP molecules for
use in all activities
• The energy is
stored in the last
phosphate bond
• ATP breaks off a
phosphate and
becomes ADP
ATP and ADP
ATP = Fully Charged
Battery
ADP = Partially Charged
Battery
What good is heat?
• Helps us maintain our
body temperature
• Speeds up reactions
in our body
• It is part of our ability
to maintain
homeostasis
Atomic Particles
Particle
Location
Charge
Mass
Proton
Nucleus
+1
1 amu
Neutron
Nucleus
0
1 amu
Electron
Orbitals
-1
0 amu
Common Elements
(p30 in 9th)(p28 in 8th)
Elem
• O
• C
• H
• N
• Ca
• P
%
At #
65.0% 8
18.5% 6
9.5%
1
3.2%
7
1.5%
20
1.0%
15
• The number of
protons identify the
element and is the
same as the
atomic number
• The atomic mass is
the number of
protons plus the
number of
neutrons
Diagram C, H, N, O, P, S
Isotopes
• Iso=same
• Same element;
different atomic
mass
• Same number of
protons
• Different number of
neutrons
Radioisotopes
• Heavy isotopes tend
to decompose to the
lighter form
• The decay is called
radioactivity
• Used to “Tag”
biological molecules
(PET scan)
• Treatment of certain
localized cancers
Types of Bonds
Type
Formed When…
Characteristics
Ionic
Electron is
Transferred
Covalent
Electron is Shared
Between atoms
with different
electronegativity
Very strong bond
Van der Waals
Forces or
Hydrogen
Bonds
Attraction between Hydrogen bonds
oppositely charged individual = weak
regions of
many = strong
molecules
Radioactivity
• Alpha or Beta
particles or gamma
rays are given off
from the nucleus
• Alpha penetrates
the least, gamma,
most
• It is the electrons
that are sent flying
that does damage
Molecules and Compounds
• Molecules are two
or more atoms of
the same element
that are joined
• H2 or O2
• Compounds are
two or more atoms
of different
elements join
together.
• CH4 or H2O
Ionic – Electron Transferred
Covalent – Electron Shared
Van der Waals Forces (oppositely
charged regions )
Synthesis Reaction
• Two or more atoms or molecules combine
to form a larger more complex molecule
• A + B → AB
Decomposition Reaction
• When a
molecule is
broken down
into smaller
less complex
molecules
• AB → A + B
Exchange Reaction
• Involves both synthesis and
decomposition. Bonds are both made and
broken and a switch is made
• AB + CD → AD + BC
Organic vs Inorganic
Organic = Carbon
Inorganic = No Carbon
Inorganic
Properties of Water
• #1 High Heat
Capacity
• Water can absorb or
release large amounts
of heat before its
temperature changes
• Prevents temperature
changes in our body
Properties of Water
#2 Polarity
• Water molecules
have a slightly
negative charge near
the oxygen atom and
a slightly positive
charge around the
hydrogen atom.
Properties of Water
#2 Universal Solvent
• Water dissolves more
substances than
sulfuric acid because
of its polar
characteristic. It can
surround molecules of
a substance and pull
it apart.
Water Properties
• #3 Chemical Reactivity
• Can break down
molecules into smaller
less complex forms
• Hydrolysis Reaction
Hydro
=
Water
Lys
=
Splitting
Water Properties
• #4 Cushioning
• Protective
function in the
form of fluid
around sensitive
organs
• Like: the brain, or
a developing fetus
Other Properties of Water
Cohesion
• Water is attracted to
other water. This is
called cohesion.
Other Properties of Water
Adhesion
• Water can also be
attracted to other
materials. This is
called adhesion.
Other Properties of Water
Density
• Ice is less dense
than water which is
why it floats.
It expands as it
freezes
Fish can live in
water during
winter
Other Properties of Water
• Surface Tension
• Cohesion of water
molecules at the surface
of a body of water causes
the water to pull itself into
a shape with the smallest
amount of surface area
(sphere).
• Surface tension allows
water striders to 'skate'
across the top of a pond.
(Cohesion)
Other Properties of Water
• Capillary Action
• Adhesive properties of
water. Placing a straw
into a glass of water, it
'climbs' up the straw.
Molecules are attracted to
the straw molecules
(adhesion). When one
water molecule moves,
the other water molecules
follow (cohesion)
• Capillary action is limited
by gravity and the size of
the straw. Plants take
advantage of capillary
action to pull water into
the roots.
Salts
• Ionic Compound
• Dissociate in water to:
Cation + and Anion –
• Calcium and
Phosphorus (bones
and teeth) and
Sodium and
Potassium
• ELECTROLYTES
conduct current in
solution
Acids and Bases
• Acids = Proton
donor, in the form
of H+ (hydrogen or
naked proton)
• Strong acids
liberate all of their
protons
• Sour / burn
• Bases = Proton
acceptor or
dissociate to give
off OH- ions
(hydroxyl)
• Strong bases give
off all OH• Bitter / slippery
Neutralization
• Neutral pH is 7
• Combine acid and
base to neutralize
• Buffers are weak acid
and bases that
maintain pH stability
by taking up excess
H+ or OH- ions
• If blood is too acidic it
will not carry oxygen
Categories of Organic Molecules
•
•
•
•
Carbohydrates
Lipids
Proteins
Nucleic Acids
Categories of Organic Molecles
Molecule
Building Blocks
Examples
Uses
Carbohydrates Monosaccharides Sugars and
CHO
Starches
Quick Energy
Lipids
CHO
Glycerol and
Fatty Acids
Fats, Oils,
Waxes
and
Steroids
Stored Energy
Cell Membranes
Proteins
CHNO
Amino Acids
Muscle
Enzymes
Collagen
Antibodies
Help Carry Out
Cellular Activities
Nucleic Acids
CHNOP
Nucleotides
DNA, RNA
Instructions for all cell
activities
Help make proteins
Carbohydrate
Lipids
Protein
Nucleic Acid
Building Blocks
4 Groups of Organic Compounds
Enzymes
Enzymes
• Enzymes =
Catalysts that speed
up reactions in our
body
• Enzymes have a
specific job – each
fits like a lock and
key with its specific
substrate
How Enzymes Work
Four steps in the process of an enzyme working.
1. An enzyme and a substrate (the biological molecule
that the enzyme will attack) are in the same area.
2. The enzyme grabs onto the substrate with a special
area called the active site which is a specially shaped
area of the enzyme that fits around the substrate. The
active site is the keyhole of the lock.
3. A process called catalysis happens which is when
the substrate is changed ( broken down or combined to
make something new)
4. When the enzyme lets go, it returns to normal, ready
to do another reaction. The substrate is no longer the
same and is now called the product.
Can you stop them????
• Good question!
• There are many
factors that can
regulate enzyme
activity, including
temperature,
activators, pH
levels, and
inhibitors.
Any factors that affect the shape of an enzyme
affect the enzyme’s activity. What effect
does pH and temperature have on an enzymes
ability to catalyze (speed up) a reaction?
• Enzymes work well within very specific
ranges of pH and temperature. If the pH or
temperature changes to outside of the
range, the enzyme shape changes and
thus no longer works to speed up the
reaction.