Transcript biochemistry

BIOCHEMISTRY
The chemistry of Life
Chemicals that make up living things are mostly
organic macromolecules belonging to the four groups
Carbohydrates
proteins
lipids
nucleic acids
http://mset.rst2.edu/portfolios/a/abdelmessih_m/finalproject/biochempro.ppt
Organic
Molecules
Structure
monomers
Carbohydrates
C,H,O
1:2:1
Proteins
C,H,O,N,S Amino Acids
Polypeptides
Lipids
C,H,O
Complex fat
Nucleic Acids
C,H,O,N,P Nucleotides
monosaccharides
Fatty Acids
polymers
Polysaccharides
RNA, DNA
Carbohydrates
•
•
Carbohydrates have the general formula of(CH2O)n, with abundant
hydroxyl groups(-OH).
Carbohydrates can be either a single sugar, (Click) monosaccharide
like glucose, (Click) a disaccharide like sucrose, or a series of
monosaccharides
(Click) polysaccharides like Starch.
Back Table
Monosaccharides
•glucose, "blood sugar", the immediate source of energy for cellular
respiration
•galactose, a sugar in milk (and yogurt), and
•fructose, a sugar found in honey.
Although all three share the same molecular formula (C6H12O6), the
arrangement of atoms differs in each case. Substances such as these three,
which have identical molecular formulas but different structural formulas, are
known as isomers.
Back
Carbohydrates
+
Two monosaccharides can be
linked together to form a
"double" sugar or disaccharide
by Condensation reaction
The reverse reaction is
Hydrolysis where sucrose
molecule is broken down into
two monosaccharides, glucose
and fructose.
Condensation
http://www.tvdsb.on.ca/Westmin
/science/sbioac/biochem/conde
nse.htm
http://trc.ucdavis.edu/biosci10v/
bis10v/media/ch02/reaction_typ
es.html
Hydrolysis
Sucrose
+ H2O
Back Carbohydrate
Polysaccharides
Complex molecules composed of three or more monosaccharides
Starch
Glycogen
Stores glucose in plant in the form of
Stores glucose in animals
in the form of highly branched chain,
Highly branched Coiled unbranched
used for quick energy.
chain
chain
Cellulose
In the form of straight chains linked
together by hydrogen bonds.
Gives rigidity and strength
to plant cells
Back Carbohydrates
Proteins
Macromolecules or polymers constructed from one or more unbranched
chains of polypeptide .A polypeptide chain is composed of amino acids.
A typical protein contains 200–300 amino acids
The protein represented here consists of two
polypeptide chains, a long one on the left and a
short one on the right.
Amino acids (Click) are the building blocks
(monomers) of proteins. 20 different amino acids
are used to synthesize proteins. The shape and
other properties of each protein is dictated by the
precise sequence of amino acids in it.
*** The important example of proteins are
(Click) Enzymes.
Back Table
The basic structural of an Amino Acid
Hydrogen
Carboxyl Group
Amino Group
ALANINE
Functional Group
GLYCINE
VALINE
Amino acids are joined together by a (Click) peptide bond.
Back Table
Back Proteins
Amino acids are joined by condensation and a water molecule is removed. It is formed as
a result of a condensation reaction between the amino group of one amino acid and the
carboxyl group of another.The bond formed as a result between the two amino acids is
called a peptide bond and the product is called dipeptide.
http://student.ccbcmd.edu/biotut
http://plantsciences.
orials/proteins/peptide.html
http://michele.usc.edu/java/pept. montana.edu/cqlab/p
roteinformation.htm
html
Back Table
Back Proteins
Back Amino acids
Enzymes
Enzymes are (Click) catalysts. Most are proteins. Enzymes bind
temporarily to one or more of the reactants of the reaction they
catalyze. In doing so, they lower the amount of activation energy
needed and thus speed up the reaction
In order to do its work, an enzyme must unite with at least one of the
reactants(substrate). This requirement for complementarity in the
configuration of substrate and enzyme explains the remarkable
specificity of most enzymes. Generally, a given enzyme is able to
catalyze only a single chemical reaction
Back Table
Back proteins
Enzymes are organic molecules that act as catalysts.
They speed up chemical reactions by decreasing
the amount of activation energy.
Back Enzymes
Lipids
Large, nonpolar organic molecules that do not dissolve in water. They
have higher ratio of carbon hydrogen bonds ( that store energy) than
carbon oxygen bonds.
Most lipids are composed of (Click) fatty acids.
Lipids
Complex Lipids
(Click)
Steroids
(Click)
Triglycerides
(Click)
(Click)
Phospholipids
Waxes
Cholesterol
Back Table
A fatty acid is a long unbranched carbon chain with carboxyl
group –COOH attached to one end.
Ahydrocarbon
end
(nonpolar,interact
With
water
molecules)
hydrophobic
A carboxyl group
(polar,attracted to
water molecules)
Hydrophilic
Back
Unsaturated
Carbon atoms
make
double
bond.
Saturated fatty
acid
Carbon atoms
make single
bonds.
Back Lipids
Triglycerides
Three molecules of fatty acids + a glycerol molecule
Unsaturated Triglycerides
Saturated Triglycerides
Saturated fatty acids
unsaturated fatty acids
Solid at room temperature
Liquids at room temperature
Ex. Animal fats
Back Lipids
Ex. Plant seed & fruits
Phospholipids
Two molecules of fatty acids + a glycerol molecule
Hydrophilic
Head
Hydrophobic
Tails
Hydrophilic Head
http://www.wisc-online.com/objects/ViewObject.aspx?ID=ap1101
http://www.susanahalpine.com/anim/Life/memb.htm
Our cell membranes are made mostly of phospholipids arranged in a
double layer with the tails from both layers “inside” (facing toward
each other) and the heads facing “out” (toward the watery
environment) on both surfaces( lipid bilayer). The membrane serves as
barrier between the inside and outside of the cell
Back Lipids
Waxes
Long fatty acid chain+Long alcohol chain.
It forms protective layer in animal and plants
Steroids
Composed of four fused
carbon rings with various
functional groups
Ex. **cholesterol
**many animal hormones
like the male hormone
testosterone.
Back Lipids
Nucleic Acids
Very large molecules(polymers) that store genetic
information.
They composed of linked monomers called (Click) nucleotides.
DNA
RNA
Deoxyribonucleic acid
Ribonucleic acid
contains information for
all cell activities
stores and transfer the
information for protein
production
Back Table
Nucleotide Structure: Monomers of nucleic acids
Phosphate
Group
Nitrogen Base
Five Carbon
Sugar
Back Nucleic acid