Instructor
Terry Wiseth
CARBON COMPOUNDS
Exceptional bonding properties
can form covalent bonds to other carbons
ORGANIC MOLECULES
carbon chain or ring backbone
1) sugars (carbohydrates)
2) fatty acids (lipids)
3) amino acids (proteins)
4) nucleotides (nucleic acids)
serve as an energy source
serve as building blocks for macromolecules
FUNCTIONAL GROUPS
atoms or clusters of atoms bonded to the carbon backbone
Methyl groups
Hydroxyl groups
Amino groups
Phosphate groups
METHYL GROUPS
butter
fats
wax
- CH3
non-polar covalent bonds link hydrogen to carbon
water cannot form hydrogen bonds with non-polar groups
HYDROXYL GROUPS
Alcohols
sugars
-OH
water can form hydrogen bonds at hydroxyl groups
thus sugars dissolve in water
AMINO GROUPS
amino acids
proteins
-NH2 or -NH3
can combine with H+ and so act as buffers against decreases in pH
PHOSPHATE GROUPS
ATP
ADP
- P
combines with adenosine molecules
ORGANIC REACTIONS
1) Electron transfer
2) Condensation
3) Hydrolysis
ELECTRON TRANSFER
one or more electrons stripped from one molecule are donated to another molecule
ex. electron transfer phosphorylation
Kreb’s cycle
CONDENSATION
through covalent bonding, two molecules combine to form a larger molecule
covalent linkage of molecules in a reaction that can form water
starches and other polymers are formed by repeated condensation reactions
HYDROLYSIS
a type of cleavage reaction which is like condensation in reverse
molecules are cleaved into two or more parts by reaction with water
polymers are hydrolyzed to use the subunits as building blocks or energy sources
MOLECULES OF LFE
Carbohydrates
Lipids
Proteins
Nucleic acids
CARBOHYDRATES
most abundant biological molecule
Monosaccharides
Oligosaccharides
Polysaccharides
MONOSACCHARIDES
simplest carbohydrate
most are sweet tasting
dissolve readily in water
consist of 5 - 6 carbons in a ring structure
function primarily as an energy source
ribose
deoxyribose
glucose
fructose
OLIGOSACCHARIDES
short chain of two or more covalently bonded sugar units
function primarily energy transport and cell membrane operation
disaccharides have two sugar units
Lactose
milk sugar
Sucrose
table sugar
Maltose
POLYSACCHARIDES
branched chain of many sugar units
function primarily in structural support and energy storage
Starch
Cellulose
Glycogen
Chitin
STARCH
plants store sugar molecules as starch
CELLULOSE
plants primarily use cellulose as a structural molecule in cell walls
GLYCOGEN
sugar storage molecule in animals
found mostly in liver and muscle tissues
CHITIN
chitin reinforced cuticle of a tick
chitin has nitrogen atoms attached to the backbone
LIPIDS
most contain fatty acid components
long water-insoluble chains of carbon and hydrogen
dissolve readily in one another
nonpolar (ether)
do not dissolve in water
polar
lipids act as the main reservoirs of stored energy
lipids also act as structural materials in cell components
Triglycerides
Phospholipids
Waxes
Sterols
FATTY ACIDS
long carbon backbone
typically stretch out like long flexible tails when combined with other molecules
saturated fatty acids
unsaturated fatty acids
SATURATED FATTY ACIDS
solid at room temperature
single bonds only in the carbon backbone
saturated fatty acids line up in parallel giving the substance a solid consistency
butter
lard
UNSATURATED FATTY ACIDS
liquid at room temperature
oils
required in the human diet
one or more double bonds in the carbon backbone
double and triple bonds put "kinks" in the tails
does not pack together and thus imparts fluidity to substances
POLYUNSATURATED FATTY ACID
Many carbon double bonds
TRIGLYCERIDES
Butter
Fats
Oils
fatty acid tails attached to a backbone of glycerol
yield twice as much energy as carbohydrates
rich source of stored energy
thick layers of triglycerides also insulate
triglycerides are stored as fat droplets in adipose tissue
PHOSPHOLIPIDS
main components of cell membranes
backbone of glycerol
two fatty acid tails which are hydrophobic
hydrophilic "head" that includes a phosphate group
main components of cell membranes
WAXES
long chain fatty acids
tightly packed and linked to long chain alcohols or carbon rings
repel water and are solid at room temperature
plant cuticles
sebum
beeswax
STEROLS
ex:
steroids
cholesterol
hormones
lipids which have no fatty acid tails
rigid backbone of four fused carbon rings
found in cell membranes
STEROIDS
Steroids are a class of hormones which act as chemical messengers in the body
CHOLESTEROL
cholesterol gives rise to:
vitamin D
estrogen
testosterone
bile salts
PROTEINS
polymers of amino acids
20 different kinds of amino acids
CLASSES OF PROTEINS
enzymes
speed up or slow down chemical reactions
structural
muscles, bone, hoof, claw, hair
transport
cell membrane and body fluids
regulatory
protein hormones
antibodies (immunoglobulins)
body defenses and immune system
PROTEIN STRUCTURE
amino acid chains linked by peptide bonds
form polypeptide chains
sequence of the amino acid links are essential to the operating characteristics of the protein
sequence of amino acid units is unique for each kind of protein
3D STRUCTURE OF PROTEINS
The three dimensional structure of a protein plays an important role in the characteristics of how a protein functions
Fibrous proteins
Globular proteins
FIBROUS PROTEINS
organized as strands or sheets
contribute to the shape, internal organization and movement of cells
keratin
hair, fur
collagen
skin, bones
GLOBULAR PROTEINS
chains are folded into compact, rounded shapes
hemoglobin
enzymes
antibodies
3D STRUCTURE OF PROTEINS
The three dimensional characteristics of proteins is the result of differences at different levels
Primary structure
Secondary structure
Tertiary structure
Quaternary structure
PRIMARY STRUCTURE
protein shape and function arise from its primary structure
amino acid sequence
SECONDARY STRUCTURE
Secondary structure is brought about by hydrogen bonds at regular intervals along the polypeptide chain
coiled, spiral, helical pattern
Secondary structure of proteins is held in place by hydrogen or disulfide bonds
TERTIARY STRUCTURE
Tertiary structure is brought about by further interactions of the backbone resulting in more folding of the polypeptide chain
QUATERNARY STRUCTURE
Quaternary structure may involve more than one protein group called subunits
LIPOPROTEINS
blood proteins combine with cholesterol, triglycerides and phospholipids after a meal
GLYCOPROTEINS
proteins with oligosaccharides covalently bonded to them
oligosaccharide chains may be linear or branched
found primarily attached to animal cell membranes
DENATURATION
breaking the weak bonds of a protein molecule disrupts its three-dimensional shape
hydrogen bonds holding a proteins secondary and tertiary structures intact are easily broken
changes in pH
changes in temperature
ex: albumin (protein) in eggs
"egg white"
NUCLEOTIDES
consist of three components
5-carbon sugar
ribose
deoxyribose
phosphate group
nitrogen base
CLASSES OF NUCLEOTIDES
energy carriers
ATP
ADP
coenzymes
NAD+
FAD
chemical messengers
cAMP
nucleic acids
DNA
RNA
ENERGY CARRIERS
delivers energy from one site to another
ATP
adenosine triphosphate
ADP
adenosine diphosphate
COENZYMES
transport hydrogen atoms and electrons stripped from other molecules
NAD+
FAD
CHEMICAL MESSENGERS
act as chemical messengers within and between cells
cAMP
cyclic adenosine monophosphate
NUCLEIC ACIDS
four different kinds of nucleotides are bonded together in large single or double stranded molecules
sequence of the particular bases is unique to each kind of nucleic acid
genetic information is encoded in such base sequences
NUCLEIC ACIDS
RNA
ribonucleic acid
single stranded
NUCLEIC ACIDS
DNA
deoxyribonucleic acid
double stranded molecule which twists helically like a spiral staircase
hydrogen bonds hold the two strands together