Transcript Organic Macromolecules

Molecules of Life
Chemistry, I thought this was biology?
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Electrolytes
Fertilizer
Soil pH
Acid Rain
Blood pH
Hormones
What are living things made of?
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Cells
Tissues
Organs
Organ Systems
What do Living Things DO?
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Interact with environment
Grow
Obtain nutrients
Breathe
Reproduce
And, more!
To understand this, we need to know
something about… chemistry
Water: The Molecule That Supports
All of Life
Water forms Hydrogen Bonds
Unequal sharing of
electrons in water
molecules leads to
many weak bonds
between water
molecules
Figure 4-12
Cohesion and Adhesion
• Cohesion: Water
molecules stick
together
• Adhesion: Water
molecules are
attracted to other
things
Fig. 4-13
Surface Tension – a
consequence of hydrogen
bonding in water
molecules
How can we demonstrate
Cohesion and Adhesion?
Water has a very high specific heat.
It takes lots of energy to heat up and it needs to give up lots of
energy before it cools. Compared to rocks and soil, water changes
temperature slowly.
Los Angeles
(Airport) 75°
70s (°F)
80s
San Bernardino
100°
Riverside 96°
Santa Ana
Palm Springs
84°
106°
Burbank
90°
Santa Barbara 73°
Pacific Ocean
90s
100s
San Diego 72°
Oceans and lakes moderate the climate of nearby coastal areas
Cooler summers & milder winters
40 miles
Evaporative Cooling
1. The fastest moving
molecules have the
most energy
2. They evaporate
3. The average
molecule is now
slower, a.k.a cooler!
Ice Floats
(A.K.A. Low Density of Ice)
• Water below is insulated
• Fish and other life survive the winter
Figure 4-15
Ice floats because its
molecules are less densely
packed than those in liquid
water.
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Cl–
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Cl–
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Na+
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(A.K.A. Water’s ability to
dissolve other substances)
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Na+
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Water: the
solvent of life
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Salts, enzymes and other
chemicals are dissolved in
the water in cells
Water
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Cohesion & Adhesion
Moderation of Temperature
Insulation of Bodies of Water by floating ice
Solvent of life
Large Biological Molecules
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Carbohydrates
Lipids
Proteins
Nucleic Acids
Molecules in
Foods
Organic chemistry
the study of carbon compounds
“Organic” can mean:
Carbon containing
Related to life
Synthetic chemicalfree (agriculture)
Cholera bacteria
Organic Compounds
Carbohydrate
• an organic molecule
made up of sugar
molecules
• Monosaccharide
– Simple sugars
– One sugar unit
• Disaccharide
– “double sugar”
• Polysaccharide
– Long chain of sugar
units
– Complex
carbohydrates
Hi, I’m Mason Bear, your
teacher’s butter eating
chocolate lab.
Today, you are going to learn
more about lipids – my
favorite. Butter is SO
YUMMY!!!

Lipids
• Fats, oils, waxes,
steroids
• Do not dissolve in
water
Saturated vs. Unsaturated
Fatty Acids
• Saturated
• Unsaturated
What do fatty tissues do?
• Store energy for
later use
• Cushion organs
• Insulate
Proteins
• Made of amino acids
• Build muscle
• Responsible for most of
our physical and chemical
characteristics
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Skin color
Hair color
Eye color
Height
Temperament
Metabolism
Food Guide Pyramid
Acids and Bases
• Occasionally water
molecules break
into H+ and OHions
• Water is neutral (H+
= OH-)
• Acids have a high
number of H+
• Bases have a low
number of H+
The pH Scale
• pH means the “power of Hydrogen”
• Ranges from 0 (most acidic) to 14 (most basic)
Pure Water has pH = 7
Acids have a pH < 7
Bases have a pH > 7
Universal Indicator Solution
Buffers
• Resist changes in pH
• Accept H+ when solutions
become too acidic (pH is too
low)
• Donate H+ when solutions
become too basic (pH is too
high)
• Essential for maintaining
homeostasis in living
organisms
Buffer Capacity
the point at which the buffer
can no longer absorb or
contribute H+
Buffering Ability
Water vs. A Biological Substance
http://www.pearsonsu
ccessnet.com
4.4 pg 4
Enzymes lower the energy
required to start a reaction
Fig. 5-15
Fig. 5-15
Enzyme Vocab.
• Activation Energy – energy needed to
start a reaction
• Enzyme – protein that speeds up a
chemical reaction by lowering the
activation energy. Enzymes are
recycled, not used up.
• Substrate – the substance
participating in a reaction aided by an
enzyme
• Active Site – part of the enzyme that
binds to the substrate; shape is very
important
Proteins can be Denatured
• Denaturation: loss of normal shape of a
protein
•Can be caused by
heat, cold, change in
pH
•Proteins that have be
denatured don’t work
well