Download Biology 105

Chapter 3: Chemistry of Life Organic Compounds
Pgs 46-73
Student Outcomes
Describe the properties of carbon that make it
the central component of organic
compounds.
Explain the relationship between polymers
and macromolecules
Distinguish among the three types of
carbohydrates.
Student Outcomes
Distinguish among Lipids -fats, phospholipids
and steroids.
Describe the structure and function of
proteins.
Describe the components of Nucleic acids.
Organic Compounds
Covalent bonds of carbon atoms - forms
the background of a molecule
(carbon-carbon or carbon-hydrogen)
Called organic because once thought to
only be created by living things.
Carbon
Atomic Number is 6 - What does this
mean?
Carbon bonds can form 4 covalent bonds.
Ideally suited for bonding to multiple
atoms. Very strong bonds
Hydrocarbons
Carbon-Hydrogen bonds - non polar
Insoluble in water - Hydrophobic
Types of Organic Molecules
Carbohydrates
Lipids
Proteins
Nucleic Acids
Carbohydrates
Sugars, starches and cellulose
Contain Elements: CH20 (ratio)
Carbon
Hydrogen
Oxygen
Monosacharides
Glucose, Fructose and Galactose
Glucose - the most abundant sugar and
energy source of most organisms
Average American consumes about
120-130 lbs of sugar yearly.
Disaccharides
Two simple sugars combined
Maltose - (glucose + glucose)
Sucrose - Table sugar (glucose + fructose)
Lactose - Milk Sugar (glucose + galactose)
Polysaccharides
Long chain of simple sugars
– Starch - energy storage in plants, water
(hydrolysis) breaks it down into glucose units
– Glycogen - animal ‘starch’, more water soluble
than plant starch, stored in liver and muscle cells
– Cellulose - most abundant carbohydrate, we
cannot break it down
Modified Carbohydrates
Chitin - main component of skeletons of
arthropods
Glycoproteins -Carbohydrates + proteins
(found on outer side of most cells)
Glycolipids - Carbohydrates + lipids (found on
outer side of animal cells)
Artificial Sweetners
Aspartame
– 200 times sweeter than Sucrose (table sugar)
Sucralose (Splenda)
– 600 times sweeter than Sucrose
Both will pass through the digestive tract unmodified
Lugduname is 200,000 times sweeter (sweetest
compound known)
Lipids
Insoluble in water
– Fats, phospholipids, carotenoids, steroids, waxes
– Elements: Carbon and Hydrogen; Oxygen in a
smaller role
– Made of fatty acids
Saturated fatty acids
Have maximum possible number of
hydrogen atoms
Solid at room temperature - animal fat,
butter, shortening
Increased risk of cardiovascular disease
Hydrogenation
Bombarding an oil’s fat molecules with
hydrogen atoms, making it more dense,
raising its melting point, - solid at room
temperature. Known as trans fatty
acids. Partially hydrogenated oil means
that the hydrogenation process stopped
short of a full solid, reaching a more
creamy, butterlike consistency = some
margarines. (carbon-hydrogen bonds)
Unsaturated fatty acids
Carbon atoms joined together, so not fully
saturated with hydrogen
Monounsaturated fatty acids (Oleic acid)
Polyunsaturated fatty acids - multiple double
carbon bonds
Olestra
Fat substitute
– Tastes and texture is similar to fats, but as
with artificial sweeteners, will not break
down along the digestive tract.
Proteins
All proteins in a cell are called its Proteome.
Study of Protein structure/activities Proteomics
Macromolecules of amino acids
– From 9 - 8000 amino acids
Enzymes (catalysts)
Elements: Carbon, Hydrogen, Oxygen and
Nitrogen
Amino Acids
20 common amino acids
Several are essential - the body cannot
synthesize in amounts necessary so must be
obtained from diet.
Amino acids are joined together - peptide
bond
Protein structure
Different amino acid sequences will dictate
the protein’s function. A single mutation can
disrupt the entire function.
Heat can also ‘denature’ a protein’s shape,
making it useless. This change in shape is
usually non reversible. Ex: albumin (egg
white)
Kwashiorkors
Enlarged abdomen due to enlarged
liver from an accumulation of lipids and
not enough protein in the diet to form
lipoproteins
Common for a diet high in grains and
starchy foods and low on protein.
Nucleic Acids
Transmit hereditary information
DNA - Deoxyribonucleic acid
or
RNA - Ribonucleic acid
Elements: Carbon, Hydrogen, Oxygen,
Nitrogen, Phosphorous
Nucleic Acids Structure
Nucleotides that consist of
– 5 carbon sugar (deoxyribose/ribose)
– Phosphate group
– Nitrogenous base (purine /pyrimidine)
Nucleotides
ATP
– Provide energy for all cells
– Composed of adenine, ribose and 3
phosphates
Graphene-a carbon allotrope
Life after silicon
Hottest new material in electronics
A flat sheet of pure carbon rings, one
atom thick that resembles chicken wire.
Carbon
Carbon’s relationship to greenhouse
gasses???
Global Warming
4 questions
– 1) Is it really happening?
– 2) Are human actions partly responsible?
– 3) Will organisms be able to adapt (natural
selection)
– 4) Will the planet be able to correct itself
without human intervention?