SCI 150 – Chemistry

Flashcard maker : Kenneth McQuaid
capacity to do work
potential energy
stored energy due to position or chemical structure
kinetic energy
energy of motion
units of energy, work, and heat
calories or joules
1 cal=4.184 J
not the same as energy
motion of molecules
molecules moving fast
molecules moving slow
exothermic reactions
release energy
endothermic reactions
absorb energy
all of the chemical reactions that take place in a living organism
energy in =
energy out + energy stored
how to measure the energy we put into our bodies
1 Cal =
1000 cal
use energy in 3 ways
basal metabolism
specific dynamic action
all the physical work we do with our bodies
basal metabolism
the work that goes on inside our bodies to keep us alive
~1 cal/hr x kg body
specific dynamic action
energy consumed in digesting and metabolizing food
fat 4%
carbs 6%
protein 30%
what you need a lot of to live
fats/oils-9 Cal/g
proteins-4 Cal/g
carbs-4 Cal/g
fats and oils
AKA triglycerides
no double bonds
one double bond
many double bonds
example of saturated
palmatic acid
example of monounsaturated
oleic acid
example of polyunsaturated
alpha linoleic acid
naturally occurring faty acids
contain only even numbers of carbon in their chains
essential fatty acids
need them in our diet
omega-3, omega-6
saturation and melting temperature
saturated=solid at room temp. higher melting point
unsaturated=liquid at room tepm. lower melting point
iodine number
number of g of I2 that can be added to 100g of the triglyceride
lower for more saturated fats/oils
catalytic hydrogenation
taking something unsaturated and making it saturated
addition of H2 in presence of catalyst
changes melting point, texture, improves shelf life
not usually carried to completion
problem-converts remaining double bonds to unnatural structure
trans fats
very rarely occur in nature
comsumption increases risk of coronary heart disease
decreases ratio of HDL:LDL
your body can’t break down transfiguration
average US trans fat intake
product labeling
as of 2006 required to show g of trans fat per serving
0g of trans fat means < .5g per serving
produced from saturated fat in your body
insoluble in water so body wraps it in lipoproteins-HDL, LDL, VLDL for transport
2 sources of cholesterol
3 types of carbohydrates
disaccharides- sucrose, lactose
polysaccharides-starch, cellulose
2 types of glucose
beta glucose- forms cellulose
alpha glucose- forms starch
alpha linkage-gives off H2O, OH group points down
monomers coming together to make polymer
rings all lie in same plane
found in plants as amylose and amylopectin
we produce glycogen-animal starch
we can digest this due to alpha linkages
OH group points up
condensation reaction-gives off H2O
can’t digest bc of beta linkages- need cellobiase
cows, sheep, etc. can because of bacteria in their diet
we still need it in our diet-fiber
lock and key mechanism
biological catalysts
only certain substrates fit certain enzymes
substrate bonds to enzyme which breaks it into 2 pieces
combination of beta galactose and glucose
rings lie one above the other
lactose intolerance
defieciency of enzyme lactase
usually gets worse with age
lactose tolerance-recent thing
amount of production controlled by genetics
large amounts of disaccharide passed through intenstines is bad
can take lactaid to help with digestion
cellulosic ethanol
most ethanol produced is currently made from corn
corn ethanol may drive food prices up
another source-cellulose
more difficult to get sugar out
can be accomplished using several expensive methods
new plant in vonore to make cellulosic ethanol from corncobs and switchgrass
amino acids
monomers that form polypeptide polymers
20 naturally occurring amino acids
give off H2O
peptide bond
peptide bond
bond between 2 amino acids
primary structure
sequence in which the amino acids are bound together in the peptide chain
diversity of R groups
containing N
containing COOH
hydrogen bonds
hydrogen on one amino acid is attracted to an O or an N on another amino acid
makes chain bend and coil
secondary structure
confirmation in space of the amino acids in a peptide chain
usually falls into 2 categories: alpha helix, beta sheet
tertiary structure
3D folding pattern of protein
interactions of alpha helix, beta sheet, random coil
quaternary structure
more than one individual protein strand is held together
subunits fit together for a purpose
hemoglobin-contains heme, prosthetic group
2 types of proteins/polypeptides
globular-water soluble
fibrous- not water soluble
574 amino acids
complex protein in red blood cells
transports oxygen from lungs to body
molecular weight 5800 amu
disulfide bonds (cystine)
produced in pancreas
insufficient production results in diabetes
3 types of diabetes
type 1
type 2
type 1 diabetes
pancreas stops producing insulin
type 2 diabetes
mostly older people
related to obesity
can be genetic
gestation diabetes
pregnant women
body can’t use insulin
sickle cell anemia
one amino acid is wrong on 2 chains
found in people of west african descent
those who have it don’t get malaria
totally distorts protein shape
impairs hemoglobin’s ability to carry oxygen
usually fatal if not treated
alpha keratin
provides structure for specialized skin cells
found in nails, hooves, horns-hard and brittle (many cystine bridges)
found in hair and wool- soft and flexible (less cystine bridges) many alpha helixes
beta keratin
many beta sheets
provides structure for specialized skin cells
found in silk, spider webs, feathers
strong but resists stretching
also in scales, claws, and beaks of reptiles and birds
most important protein in our bodies (1/3 of our protein)
found in skin, tendons, ligaments, bones, and cornea
3 polypeptide chains helically coiled around eachother
extremely strong
protein/lipid complex to carry hydrophobic substances through the blood
sources of protein in our diet
have to have it
animal products may provide highest quality but there are still problems
plastics and polymers
very importatn in daily life
all commercial plastics are polymers
not all polymers are plastics
material capable o being shaped into virtually any form
molecule of high molecular weight formed through the repeated chemical linking of many smaller molecules (polymerization)
one of first ploymers of interest to humans
substance that stretches easily and returns back to its original shape
addition polymer
molecule adds to another molecule
no mass lost as chain extends
dominate commercial market
eg rubber
condensation polymer
two molecules combine and lose a small simple molecule in the process( usually water, simple alcohol)
eg bakelite, nylon, polyester
all of the monomers are identical
eg -x-x-x-x-x-x-x-
polymer chain composed of 2 or more different types of links
eg -x-y-z-x-y-z-x-y-z- or
resin identification codes
used in plastic recycling
condensation polymer
more properly called PET
commercial leader among condensation polymers
(food storage bags)
most important polymer in US
first prepared in 1934
two types: low density and high density
low density polyethylene
short unbranched chains off the main branch
low melting point, low density
tangled mess
flimsy trashbags
high density polyethylene
produced in early 1950s
prepared with organometallic catalysts that control the way monomers lonk as they are polymerized
containers holding liquid
homopolymer and addition polymer chains can be isotactic-all on same side, syndiotactic-alternating sides, atactic-random auto trim, carpet, harder plastics
polymerization of vinyl chloride makes a tough plastic (PVC)
used to make construction materials
can be brittle
chemicals are added to soften the plastic(plasticizer)
these can leach out over time
polymers similar to PVC
polyvinylacetate-safety glass, chewing gum
homopolymer and addition polymer
olefin-old word for alkene
lightweight used to make cheap plastic stuff
revolutionalized rubber industry
natural rubber has some problems: high temp turns it sticky, no longer an elastomer
serendipity: 1839 goodyear accidentally spilled a mix of rubber on a hot stove which resulted in a very elastic substance
vulcan- god of fire
sulfur cross linked the poly-isoprene chains resulting in a much more useful material
rubber replacements
synthetic elastomers-
styrene butadiene rubber(tire treads)
neoprene (gaskets, auto parts, construction material)
brittle polymer formed from nitrocellulose
originally used as artificial ivory
used to make photo film, ping pong balls, knife handles
largely been replaced due to its flammability
thermosetting polymer-not plastic after formed
resistant to heat and electricity
used in construction materials
invented in 1930s at dupont
several different versions
condensation polymer
benefits of nylon
can be drawn out into long, strong, silky fibers useful in textiles
used in toothbrush bristles and stockings
rationed for the war effort
polycarbonate/bisphenol A
found in applications that require high temp resistance and impact resistance (baby products)
BPA mimics estrogen in the body
currently being evaluated as carcinogen
can harm reproductive organs
research ongoing
inorganic polymers
not as common commercially-geologically important
asbestos-dangerous, causes lung cancer, doesn’t burn
in real life
polymers you come in contact with are often copolymers or mixed with additives to give better properties to the material
our economy and society is built around polymers
important to polymer industry to keep cost of oil low
substance applied directly to the human body to make it more attractive
hydrophobic-doesn’t like water
hydrophillic-likes water
long chain of hydrocarbons )hydrophobic) connected to an ionic “headgroup”(hydrophillic)
when put in water it will accumulate at surface to accomodate both ends
surface tension
why water forms droplets or beads
how soaps work
surface active agent- surfactant
cleans by:
decreasing surface tension of water
soaps and detergents
all soaps are detergents
not all detergents are soaps
common surfactants
sodium lauryl sulfate
ammonium lauryl sulfate
triethanolammonium lauryl sulfate
all detergents
cortex-2 pigments: melanin and phaomelanin
stratum corneum-outer layer of skin
eccrine sweat gland-controls temp
apocrine sweat gland-makes you stink, bacteria ferments fluid
sebacceous gland-produces oil
made mostly of proteins
pH of hair
at pH of 4-6 tight cuticle, reflects light coherently, hair shines
at higher pH ruffled cuticle, scatters light, hair looks dull and flat
typical shampoo
water 60%, surfactnt 30%, acid 4%, conditioners 2%, fragrance 1%, formaldehyde .5%, other .5%
hard vs soft water
hard-contains salts of calcium, magnesium, and iron
combine with fatty acid anions and make soap scum
tis wastes soap and makes clothes look dull
can be fixed with water softener(Na+)
some commercial detergents have been developed that don’t react in hard water
hair color
historically people used plant extracts and colored metals
now we use complex organometallic compounds
temporary-large molecules, easy to wash
semipermanent-smaller molecules diffuse into cortex
permanent-2 molecules combine in cortex to make a larger molecule that can’t escape
curing hair
hair’s shape depends on arranement of chemical bonds within keratin
can have disulfide bonds(strongest), hydrogen bonds (weakest), or salt bridges
to change shape-break bonds, form hair, reform bonds
wet/dry style-wet hair, roll hair, dry hair
perms-2 chemicals: thioglycolic acid-smelly, peroxide
2 pigments in hair cortex
hair color depends on ratio of 2 pigments
brazilian blowout
put keratin on hair then flat iron for 2-3 hours
lasts 3 months
can be dangerous
protected by thin layer of hydroxyapatitie
plaque sticks to your teeth and harbors bacteria
bacteria produce acid that erodes surface of teeth
with daily removal of plaque, teeth can remineralize
you want something that scrapes away plaque, but not surface of teeth
fluoride-replaces hydroxly groups with fluorine making fluoroapetite
can cause fluorosis
skin care products: lotions
they are emulsions
usually contain mineral oil, wax, and water
locks in moisture
way of controlling body’s temp
2 types of sweat glands-eccrine, apocrine
contain alluminum that shrinks sweat glands
reduce bacteria that causes odor
mask odor and kill bacteria with antibiotics
cosmetics that add color
lipstick-contain special formulation of oils, waxes, hydrocarbons to give it texture
only small % is color
mascara-colors light tips of eyelashes to make them look longer
guanine-same chemical as in bat poop but bat poop not in mascara
4000 natural compounds
2000 synthetic compounds
chemical value
chemicals themselves are neither good or bad
value lies in how we use them
harmful sustance that can cause illness or death when it enters our bodies
poison with a biological origin
examples of poisons
water, salt, nutmeg, ethyl alcohol, aspirin, potatoes
lethalness depends on
chemistry of the substance-whait does in the body
how much of it we are exposed to
how we are exposed-food,skin,air
how susceptible we are as humans
how susceptible we are as individuals
estimating lethal quantities
give substance to lab rats/mice and see how many die
due to differences and in order to get a statistical sampling-use large numbers
ethical issues
LD50 of a substance
amount that kills exactly 1/2 of a large population of animals
naturally occurring toxins
clostridium botulinim
muscarine chloride
tubocurarine chloride
man made poisons
nerve gases
sodium cyanide
prescribed to pregnant women in europe as sleeping pill
passed several routine toxicological screenings
was not approved
produced thousands of birth defects
two forms- one causes defects one is a sedative
taken off market until recently
inhibits TNF-alpha
found to aid in leprosy, HIV/AIDS,
acceptability of risk
government safety related offices
moecules of the day:
isolated from bark of south american tree
has bitter taste
ingredient in tonic water
fluoresces under black light
used to treat malaria
200 times sweeter than sucrose
not metabolized by body
stable at high temp
slightly bitter aftertaste
aka ACE-K
acesulfame potassium
found in beer
found in watermelon
has insecticidal activity
cockroach repellant activity
old man smell
discovered in 1938 by Dr Roy Plunkett
revolutionized polymer industry
most slippery material in existence
registered trademark of dupont
soil and stain repellant
nonstick cookware coating
poltetrafluoroethylene- PTFE
aka teflon
absorbed in small intestine and metabolized in liver
increases risk for serious side effects including deep vein thrombosis
one of the most commonly used medications
found in most combination birth control pills and the patch
can be produced from glycerol by bacterium acetobacter
reacts with proteins in stratum corneum to produce a brown color
an essential amino acid
some individuals are unable to metabolize this
metabolic by-product of aspartame
originally developed to treat hypertension and angina
clinical trials showed that it had interesting side effects in males
patented by pfizer in 1996 to treat ED as little blue pill
has become popular drug worldwide
sildenafil citrate
aka viagra
approved by FDA in 1950s
thins mucous and lubricates airway
often packages with antihistamines
naturally occurring metabolite of vitamin a
decreases secretions and size of sebaceous glands
accused of causing depression, psychosis, and suicide
used to treat severe acne
developed by US army in 1946
contained in 230 consumer products
used as pesticide
in products like off, repel etc
aka DEET

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