The Organic Molecules of Life
Organic Molecules
Molecules that have carbon (C) as central element
All life is based on carbon!
Why is carbon so important to life?
Is carbon stable, or will it want to bond with others?
In how many places will it bond with others?
Will it form weak ionic or strong covalent bonds?
Carbon can form large, complex, and stable
molecules!
Shape is important!
Why is shape important?
Body recognizes
different molecules
by recognizing
different shapes
Global Warming: It's All About Carbon
http://instruction2.mtsac.edu/jkido/Biology%201/Anim
%20&%20Videos/Exam%201/exam1_anim_videos.html
Large Organic Molecules Found in All Cells
Carbohydrates, Proteins, Lipids, & Nucleic Acids
Large Organic Molecules Found in All Cells
Carbohydrates, Lipids, Proteins, & Nucleic Acids
Most of these large molecules are made up of
smaller molecules called monomers. These
large molecules are also called polymers
because they are made up of many monomers
linked together.
monomer + monomer + monomer = polymer
Making and Breaking (Digestion) of
Polymers
Carbohydrates – “sugars” made up of C,
H&O
Monosaccharides (simple sugars)
One sugar molecule (monomer building block)
Monosaccharides
Function?
Disaccharides
2 monosaccharides bonded together
Function?
Disaccharides
2 monosaccharides bonded together
Galactose
lactose
Glucose
Polysaccharides (complex carbs)
Many monosaccharides
(monomers) bonded
together to produce
long chains (polymers)
What monosaccharide makes up these
polysaccharides?
What is produced when starch is broken down?
Polysaccharides (complex carbs)
Many monosaccharides
(monomers) bonded
together to produce
long chains (polymers)
Read p. 47-48
“Complex
Carbohydrates”
Proteins
Proteins
Monomer unit?
Chain of
amino acids?
Polypeptide that
has folded into a
certain shape?
Different arrangements of the 20 amino
acids can make many different proteins
Importance of Amino Acid Sequence
Importance of Protein Shape
Shape enables protein to carry out specific job
Four Levels of Structure in Proteins
(a) Primary structure
amino acid sequence
(b) Secondary structure
alpha helix
beta pleated
sheet
(c) Tertiary structure
(d) Quaternary structure
random coil
folded
polypeptide
chain
two or more
polypeptide
chains
Proteins need to maintain their shape in
order to function properly
How can proteins lose their
shape (denature)?
Enzymes
Function?
High Density Lipoproteins (HDLs) vs. Low Density
Lipoproteins (LDLs)
Good vs. Bad Cholesterol
Lipids – fats, oils, phospholipids, & steroids (also
made up of C, H & O)
Mainly what two elements?
Do not have monomer/polymer structure
Lipids – fats, oils, phospholipids, & steroids (also
made up of C, H & O)
Do they dissolve easily in water?
Fats & Oils (Triglycerides)
3 fatty acid tails linked to a glycerol head
Fats & Oils (Tricglycerides)
Functions?
1 lb. of fat packs more than twice as much
energy as 1 lb. of carbohydrate
Saturated Fats
Palmitic acid
saturated
Double bonds?
Saturated with hydrogens?
Straight or crooked tails?
Will they lie flat & pack together tightly?
Will they remain a liquid or solidify?
Sources?
Unsaturated Fats
Double bonds?
Saturated with
hydrogens?
Straight or crooked tails?
Will they lie flat & pack
together tightly
Will they remain a liquid
or solidify?
Sources?
Oleic acid
monounsaturated
Linoleic acid
polyunsaturated
What are hydrogenated (trans fats) or
partially hydrogenated oils?
Palmitic acid
saturated
Oleic acid
monounsaturated
Linoleic acid
polyunsaturated
Which type is healthier for you and why?
Read p. 54-55 Essay “From Trans Fats to
Omega-3s: Fats and Health”
Phospholipids
Consist of 2 hydrophobic
fatty acid tails linked to a
hydrophilic phosphate
group head
Function?
Steroids
Carbon skeleton bent into 4 fused rings
Cholesterol
What does cholesterol do?
Function: is a component of cell
membranes & is needed to produce
sex hormones (testosterone &
estrogen)
How do we get cholesterol?
What organ produces it?
What foods contain it?
Sex hormones:
(testosterone, estrogen,
progesterone)
Functions?
Anabolic Steroids
What natural hormone
are they structurally
similar to?
Will they mimic its
effects?
Effects?
Cause body to reduce
normal output of sex
hormones
Hathaway, J. & J. PhilpotThe Science Quarterly Review 2005
Nucleic Acids
Monomer unit?
Nucleotide
Nucleotides composed of:
1. Sugar
2. Phosphate
3. Base
DNA (Deoxyribonucleic Acid)
Shape is like a twisted
ladder
Sugar & phosphates make
up sides of ladder and bases
are the rungs
Bases = Adenine, Guanine,
Cytosine, Thymine
2 nucleotide strands are
twisted around each other
= double helix
Functions of DNA
Contains many genes
Genes are instructions for making specific
proteins
amino acid sequence
alpha helix
beta pleated
sheet
folded
polypeptide
chain
two or more
polypeptide
chains
random coil
Functions of DNA
Genetic material passed on to
offspring
In humans, 3 billion nucleotides
make up a single DNA molecule.
And, every one of our cells that
has a nucleus contains one of
these 3 billion nucleotide long
molecules.
RNA – Ribonucleic Acid
Double or single
stranded?
Same bases as DNA?
Function: Comes in
several forms and is
involved in making
proteins
Types of Organic Molecules
Carbohydrates, Lipids, Proteins & Nucleic Acids
All living organisms are made up of these!
What macromolecule is a type of lipid?
A. Starch
B. DNA
C. Sucrose
D. Enzymes
E. Steroids
What monomer units make up proteins?
A. Nucleic acids
B. RNA
C. Monosaccharides
D. Amino acids
E. Enzymes