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Molecules of Life
Molecules of Life
Organic Compounds: Molecules containing the element of carbon and at least one hydrogen
atom.
•Chemistry of Carbon Atoms
•Carbon atoms form chains
•Carbon chains are backbone for molecules of life
Functional Groups: particular atoms or clusters of atoms covalently bonded to carbon.
Organic MoleculesContain Carbon
and often hydrogen, oxygen, and other atoms
Everything here is organic
…..oops except for the bottle
Biologically Important Organic Molecules
Hydrocarbons – C, H
Carbohydrates – C, H, O
Proteins – C, H, O, N, S
Lipids – C, H, O
Nucleic Acids – C, H, O, N, P
Hydrocarbons contain carbon (C) and hydrogen (H)
HC
Hydrogen atom
Carbon atom
H
H
H
H
C
CH4
Methane = simple
hydrocarbon
A simple organic molecule with 1 Carbon and 4 hydrogen atoms
Energy released when hydrogen separated from carbon during burning
Ethane
Propane
Examples of Hydrocarbons (carbon and hydrogen)
Butane
Hydrocarbon (carbon and hydrogen)
Gasoline
Diesel – long chain hydroc-c-c-c-c-c-c-carbon
Monomers
Dimers
Polymers
What are monomers?Monomers = small molecules linked together to form chains.
What are polymers?Polymers = monomers linked together in chains .
Poly = many mer = parts or units Polymer = many parts linked together
?
Like a polymer
Like monomers
OH HO
O
Dehydration (removal of water) synthesis (uniting)
Monomer A
HOH
(Monomer A) (Monomer B)
(Monomer B)
Dimer & Polymer formation
(Monomer A)
dimer = two monomers
Carbohydrates
Contain
Carbon
Hydrogen
Oxygen
Biologically important
organic compounds
Carbohydrates
Proteins
Lipids
Nucleic Acids
Monosaccharides = sugar
Ex. Glucose, Fructose, Galactose
Dissaccharides
Ex. Sucrose
Polysaccharides
Ex. Starch and Glycogen
(long chains of glucose molecules)
Carbohydrates
CARBOHYDRATES
Function: quick energystructural support
Characteristics: H – C – OHratio of carbon to hydrogen to oxygen atoms is 1:2:1
Monomer is the monosaccharide
Chapter 3The Molecules of Cells
Chapter 3The Molecules of Cells
Chapter 3The Molecules of Cells
Chapter 3The Molecules of Cells
Starch is a polymer of glucose used for storage. It is found in plants.
Cellulose is a polymer of glucose - used for storage. It is found in plants. We cannot digest cellulose!
Chapter 3The Molecules of Cells
Glycogen is a polymer of glucose used for storage. It is found in animals.
Chapter 3The Molecules of Cells
Contain
Carbon
Hydrogen
Oxygen
Nitrogen
(Sulfur)
Biologically important
organic compounds
Carbohydrates
Proteins
Lipids
PROTEINS:Structure and Function of proteins controls structure and function of all life
Amino Acids
Dipeptide
Polypeptide or Protein
Proteins
Chapter 3The Molecules of Cells
Proteins
Characteristics
The monomer form is called an an amino acid.
A central or alpha carbon which is connected to the following:
amino group
carboxylic acid group
hydrogen
R-group
Chapter 3The Molecules of Cells
Proteins
Chapter 3The Molecules of Cells
Proteins
These 20 different amino acids are analogous to an alphabet with 20 letters
Each letter can be put together in any order, for any length to form an infinite number of proteins (words)
Chapter 3The Molecules of Cells
Proteins
What process do you use to form a peptide bond?
NCC – NCC – NCC- NCC - NCC
Chapter 3The Molecules of Cells
Proteins
Functions
Structural – bones, muscles, collagen
Enzymes – proteins which speed up chemical reactions
Transportation – hemoglobin within your red blood cells transports oxygen to all parts of your body
Protection – antibodies enable you to fight off infections
MORE MORE MORE!
Contain
Carbon
Hydrogen
Oxygen
Biologically important
organic compounds
Carbohydrates
Proteins
Lipids
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LIPIDS
Function: long term energy
storageinsulationprotective cushionforms cell membraneshormones
Characteristics: do not dissolve in waterno simple monomer
structureTypes
Fats and OilsPhospholipidsSteroids
Chapter 3The Molecules of Cells
LIPIDS – Phosopholipid
Chapter 3The Molecules of Cells
Lipids (fats) = polymers made of monomers
called fatty acids and glycerol
glycerol
Fatty acid
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LIPIDS – Fats and Oils
What atoms are these molecules made of? Are these molecules hydrophobic or hydrophilic?
Triglyceride
Chapter 3The Molecules of Cells
LIPIDS – Triglycerides
Saturated fats – no double bonds exist in the fatty acid tails
Unsaturated fats – have at least one carbon – carbon double bond in any of their fatty acid tails
What is the difference between oil and butter?
Chapter 3The Molecules of Cells
Saturated vs. Unsaturated Fat
•
LIPIDS – Other Lipids
Chapter 3The Molecules of Cells
Steroids are lipids which possess a “ringed” structure
Cholesterol is a major component of the cell’s plasma membrane (structural function), but it is also the precursor for the key hormones testosterone & estrogen
Proteins as Enzymes
Models of Enzymes
How do enzymes work???
The Role of the Enzyme-Substrate Complex
Figure 5.5A Jumping-bean analogy for energy of activation (EA) and the role
of enzymesEA barrier
Reactants
Products1 2
Enz
yme
EN
ER
GY
LE
VE
L
Progress of reaction or time
Rat
e of
rea
ctio
n
Temperature (C)
0 20 40 60 80 100
Enzyme A Enzyme B
Environmental factors affecting enzyme activity
Environmental factors affecting enzyme activity
Optimal pH for two enzymes
Ra
te o
f re
act
ion
Ra
te o
f re
act
ion
0 20 40 60 80 100Temperature (Cº)
(a) Optimal temperature for two enzymes
(b) Optimal pH for two enzymespH
Optimal temperature fortypical human enzyme
Optimal temperature for enzyme of thermophilic
Optimal pH for pepsin (stomach enzyme)
Optimal pHfor trypsin(intestinalenzyme)
10 2 3 4 5 6 7 8 9 10
(heat-tolerant) bacteria
Contain
Carbon
Hydrogen
Nitrogen
Oxygen
Phosphate
Biologically important
organic compounds
Carbohydrates
Proteins
Lipids
Nucleic Acids
Nucleic Acids
Function: make up genes which
store all of the information about
an organismenergy currency of the cell
Characteristics: monomer is a nucleotide5- carbon sugarphosphate group1 of 5 nitrogenous bases(adenine, cytosine, thymine, guanine, or uracil)
Chapter 3The Molecules of Cells
Nucleic Acids
Chapter 3The Molecules of Cells
Nucleic Acids
Chapter 3The Molecules of Cells
Nucleic Acids
Chapter 3The Molecules of Cells
Nucleic Acids
Chapter 3The Molecules of Cells
Nucleic Acids
Chapter 3The Molecules of Cells
A = T
G = C
Nucleic Acids
Chapter 3The Molecules of Cells
Nucleic Acids
Chapter 3The Molecules of Cells
Types of nucleic acids
DNA – deoxyribonucleic acid
Deoxyribose
Phosphate group
Adenine, guanine, thymine, cytosine
Double-stranded structure (double helix)
RNA – ribonucleic acid
Ribose
Phosphate group
Adenine, guanine, uracil, cytosine
Single-stranded linear structure
Chapter 3The Molecules of Cells
ATP – adenosine triphosphate
Ribose
3 phosphate groups - the terminal or last phosphate is held on by a high energy but weak bond – when this bond is broken energy is released
Adenine
Nucleic Acids
RECAP
How do monomers become polymers?
Chapter 3The Molecules of Cells
Dehydration synthesis – Removal of a water molecule between two reacting molecules forming a new covalent bond in the process
How do polymers become monomers?
Chapter 3The Molecules of Cells
Hydrolysis – Addition of a water molecule to a polymer to break a bond within a polymer to form the monomers
