Download biochemistry-16

You are what you eat!?
Chemistry – study of what substances are
made of and how they change and combine.
• Each different kind of atom is a
different element.
Examples of elements:
C – Carbon
H – Hydrogen
O – Oxygen
N – Nitrogen
• Two or more elements combine to
make a compound.
Examples of compounds –
H2O, CO2, HCl, NaCl
• Compounds are classified into 2 groups:
1. Inorganic Compounds – come from nonliving
substances (In = not Organic = living)
Ex: H2O is the universal solvent because of its bent
molecular shape and polarity. Water dissolves
other polar compounds by pulling them apart like
a magnet separates metals.
Positive and
negative
ends like the
poles of a
magnet.
*70-80% of your body is water
2. Organic Compounds – come from living
substances
Biochemistry – study of the chemistry of living organisms
• All organic compounds will have the element carbon in them
Exception: CO2 is not organic (CO2 is not
composed of living substances.)
• Organic compounds are usually complex compounds with
many atoms in their structure.
Ex: Glucose – C6H12O6
• Four kinds of organic compounds:
1. Carbohydrates
2. Proteins
3. Lipids
4. Nucleic acids – DNA and RNA
Note:
***Polysaccharides are composed of
monosaccharides bonded together.
Polysaccharides must be first broken
down to monosaccharides for cells to
use as energy.
Carbohydrates
Function
• first and preferred energy
source of cells
• structural support in
plants
Structural Formula
of Monosaccharide:
Examples
Composition /
Structure
• monosaccharides – (one
sugar)
Ex: glucose, fructose
• polysaccharides – (many
sugars)
Ex: starch ***
• plant starch
Ex: pasta, bread, rice
• cellulose – gives plant
cells rigidity and gives us
fiber in our diet
• Ratio – 1C:2H:1O
Ex: Glucose – C6H12O6
• How are large
macromolecules formed?
Smaller sugars combine
to make larger
molecules.
• control rate of reactions
• form bones and muscles
• transport substances in
and out of cells
• fights disease
Proteins
Function
Structural
Formula of Amino
Acid:
Examples
(not in the reading)
Structure
• food examples from
animals – eggs, milk,
meat
• food examples from
plants – nuts, beans
• enzymes
• elements involved –
C, N, H, O
• proteins are composed of
– amino acids
• How many different
amino acids are there?
20
General Structure
of Amino Acid
Alanine
Serine
Protein
Amino Acids
Lipids
Function
• store energy – provides
more energy per gram
than carbs
• part of cell membranes
and waterproof coverings
Structural Formula
of Lipid:
Examples
Diet info
(to be covered in class)
•
•
•
•
fats
oils
steroids
waxes
• saturated – contains only
single bonds, solid at
room temp.
• unsaturated – contains
double bonds, liquid at
room temp. (Better for
your diet.)
Function
• store and
transmit genetic
information
(parent to
offspring)
Examples
• DNA
• RNA
Nucleic Acids
Enzymes
• Catalyst—substance that accelerates the rate of a
chemical reaction
Ex: hydrogen peroxide being broken down into water and oxygen
H2O2
H2O + O2 add catalase for FASTER REACTION!
•
•
•
•
•
•
•
Enzyme – a kind of catalyst found only in living things
Enzymes are proteins
Enzymes change only the speed of the reaction
Enzymes are never used up in a reaction, so they can be used
over and over
Enzymes are specific for the reaction they catalyze
Ex: Saltines and amylase
Starch
Sugar
Enzymes allow digestion to occur faster; otherwise the
hamburger you ate last week might still be in your stomach!
By using enzymes to break chemical bonds in food molecules,
organisms release energy for life processes