A&P Chemistry Flashcards
Atomic number
Total number of protons in an atom
determines what type of atom it is
NO 2 elements with the same number of protons
Atomic number and electrons
Atoms usually contain the same number of protons and electrons
Mass number
Total number of protons and neutrons in an atom
Element
Substance composed only of atoms with same atomic number
Isotopes
Atoms with same number of protons but different numbers of neutrons
Different mass number
Atomic Mass
Actual mass of an atom of a specific isotope
Measured in atomic mass units (amu) or daltons
One amu = 1/12 mass of a carbon-12 atom
1 amu = Very close to the weight of one proton or one neutron
Atomic Weight
average mass of an element, including different isotopes in proportion
avgmass of all the isotopes of an atom
close to mass number of most common isotope
elements
118 total known elements, 94 natural, 24 can be physically or chemically derived
make up both living and non-living matter
Four elements account for 96% of elements in the body
Oxygen (65%)
Carbon (19%)
Hydrogen (10%)
Nitrogen (3%)
CHON
8 elements = 3.8%
Sulphur, sodium, chlorine, calcium, phosphorus, iron, magnesium, & potassium
SSCCPIMP
Trace elements (<0.2%) of others
aluminum, boron, fluorine, zinc, iodine, tin, selenium, chromium, cobalt, copper, manganese, molybdenum, vanadium
Atoms are electrically neutral
Every positive proton is balanced by a negative electron
unfilled valence shell
Atoms with unfilled valence shell are reactive and tend to react with other atoms to fill outer shell
full outer shells are inert
Do not readily react with other atoms; more stable
Atoms that have gained or lost electrons are no longer electrically neutral and become…
ions
positive ion
Called a positive ion or cation
negative ion
Called a negative ion or anion
difference between a molecule and a compound
Molecules = when 2 or more atoms share electrons and form chemical bonds
Compounds = a combination of 2 or more different elements
all compounds are molecules, Not all molecules are compounds
chemical bonds
Ionic bonds
covalent bonds
hydrogen bonds
chemical bonding
atoms want to fill there valence shells by either receiving, donating, or sharing electrons
This creates chemical bonding
Chemical bonding creates molecules
Ionic bonds
electrical attraction between cations and anions
Involve transfer of one or more electrons from one atom to another to achieve stability
Ionic bonds are…
These are relatively strong when NOT in solution, but VERY weak when placed in solution
When molecules with ionic bonds are placed in solvent (water) they tend to dissociate (break apart) into ions
electrolytes
When molecules with ionic bonds are placed in solution they tend to dissociate (break apart) into ions
These ions are then called electrolytes
Example: NaCl dissociates into the electrolytes Na+ & Cl-
When molecules with ionic bonds are placed in solution (water) they tend to dissociate (break apart) into ions, which are called…
electrolytes
Covalent bonds
Involve sharing of electrons between atoms
VERY STRONG bonds (compared to ionic bonds)
single, double, triple covalent bonds
Nonpolar covalent molecules
polar covalent molecules
NONPOLAR
Electrons shared equally between atoms
No electrical charge on the molecule
Therefore, do not interact with other molecules
POLAR
Electrons are NOT shared equally between atoms
Forms because one atom has a stronger ‘pull’ on the electrons
electronegativity
one atom has a stronger ‘pull’ on the electrons
Electronegativity: how strongly an atom attracts a bonding pair of electrons to itself
electronegativity is affected by…
Atomic radius:
Smaller = greater electronegativity
Nuclear charge:
more positive = greater electronegativity
Hydrogen bonds
a polar covalent molecule containing hydrogen
force of attraction between a partially positive hydrogen atom in a polar molecule and another molecule or atom with a partial negative charge
WEAKEST of the bonds discussed
The hydrogen bonds between water molecules = specific properties
Surface tension
Heat capacity
water acts as a solvent
periodic table rows
periodic table groups
horizontal “rows” = periods/series
Each element in the same period has the same number of electron shells
vertical “groups” =
Each element in the same groups has the same number of valence electrons
except helium = 2 valence e
of electrons
find on periodic table:
Atomic symbol
Atomic #
Atomic mass (weight?)
# of protons
find on periodic table
Isotopes
Atoms with same number of protons but different numbers of neutrons
Different mass number
Radioactive isotopes
isotopes that are highly unstable and therefore are prone to decaying which causes radioactivity
Half-Life
Half-life = time required for half of the radioactive atoms in a sample of that isotope to decay into a more stable form
Some are days, others may be 1000s of years
Free Radicals
Atoms/molecules with an unpaired electron in its outermost shell
Free radicals are produced in normal metabolic processes
are highly reactive and can damage the body
ways to remove free radicals
Enzymes
Antioxidants
Antioxidants
such as vitamin E, carotene, lycopene
If the production of free radicals overwhelms the body’s ability to deal with them, damage can occur
too many free radicals, reasons
sunlight
Ozone
Smoke
heavy metals
Radiation
Asbestos
other toxic chemicals
what do free radicals do?
Free radicals ‘steal’ electrons from other molecules by a process called oxidation.
“OXIDATIVE STRESS”
oxidizes molecule
causes cellular damage
Oxidation is Loss (of electron)
Reduction is Gain (“)
chronic diseases are the direct result or correlated with oxidative stress
types of chemical reaction (2 types, and 5 examples)
exergonic and endergonic chemical reactions
types of chemical reactions:
Anabolic
Catabolic
Exchange
Reversible
Redox
understand how “Chemical Reactions” are different from “Chemical bonds” and how they’re related
Chemical Reactions are…
chemical changes which form new substances
Chemical bonds in the reactants (reacting molecules) are broken; this takes in energy.
New chemical bonds form to make the products; this gives out energy.
reactants (starting) –>
products (end)
exergonic vs endergonic reaction
If a reaction releases energy it is called an exergonic reaction
REACTANTS –> Energy + Products
If a reaction absorbs energy it is called an endergonic reaction
ENERGY + REACTANTS –> Products
exergonic, endergonic reaction (specific examples)
Digestion
Glycolysis (breakdown of glucose which yields ATP)
endergonic:
Synthesis reactions such as creating glycogen from glucose (storing excess glucose)– glycogenesis
Activation Energy
All chemical reactions require an initial amount of energy to occur (activation energy)
efficient chemical reactions =
By coupling reactions, this allows the body to utilize the energy released in the most efficient way possible
the energy released from 1 reaction is used to fuel another
Energy is never created or destroyed but simply converted to another form (law of conservation of energy)
two ways to make chemical reactions more efficient
coupling reactions
catalysts (enzymes) – lower activation energy
catalysts (e.g. enzymes)
substances which increase the rate of reactions without being consumed themselves (e.g. enzymes)
One way these work is by lowering the activation energy
Anabolism (Synthesis reactions)
endergonic
use up energy by joining small molecules (“building up”) to make larger/more complex ones
Anabolism is powered by catabolism (uses nutrients from the food we digest to build the tissues and organs we need to grow and repair)
synthesis reaction (Dehydration synthesis)
Dehydration reactions are a type of anabolic reactions
(Dehydration synthesis)
Formation of a complex molecule by removing a water molecule
Catabolism
decomposition reaction
Breakdown of nutrients for absorption into cells and tissues for immediate body use
Decomposition Reaction (Hydrolysis)
water breaks down molecule
Components of water molecule (H and O H) are added to the fragments
majority of catabolic reactions in the body are hydrolysis reactions
Exchange Reactions
cations and anions that were partners in the reactants are interchanged in the products
exchange reactions, the products must remain electrically neutral
AB + CD –> AD + BC
Reversible Reactions
eversible reaction is constantly going between reactants and products
At equilibrium, the rate of each reaction is equal
Reversible reaction example
Glycogen breaks down into glucose + ATP during catabolism (when you need energy)
But in anabolism (when you have excess energy), glucose is converted to glycogen for storage (to be used another time)
glycogenolysis
glycogenesis
exchange reaction example
Rust (Fe2O3) can be dissolved by hydrochloric acid (HCl)
“buffer” systems to stop the body from becoming too acidic
Oxidation-Reduction Reactions (REDOX)
reactions that are concerned with the transfer of electrons between atoms and molecules
Oxidation refers to the loss of electrons; in the process the oxidized substance releases energy
Reduction refers to the gain of electrons; in the process the reduced substance gains energy
oxidation reduction reaction example
When a food molecule, such as glucose, is oxidized, it produces energy
inorganic compounds
organic compounds
Inorganic compounds include compounds NOT containing carbon and are usually simple, this includes water
Organic compounds ALWAYS contain carbon and hydrogen
May contain other elements as well, but must contain carbon and hydrogen
organic compounds must contain…
carbon and hydrogen
Fluid distribution in the body
In males = approximately 60% of body mass
in females = approximately 55%
fluid composition
2/3 of the water in the body is intracellular (Cytoplasm)
1/3 is extracellular
extracellular fluid composition
(80% of ECF) Interstitial/intercellular
fluid in between cells, BUT not in the blood
(20% of ECF)
Plasma
the liquid component of blood – only in blood vessels
water properties
Acts as a solvent
Acts as a chemical reactant
High heat capacity
Acts as a lubricant
solvent and solute
Solutions are made up of solvents (the liquid factor) and solute
water as solvent in ECF & ICF
O2, CO2, glucose, electrolytes, hormones, etc
storing/transporting molecules:
1) Gases like oxygen and carbon dioxide
2) Nutrients such as glucose
3) Electrolytes like Na+ and Cl- that are essential to bodily functions
4) Hormones which send signals throughout the body
NaCl vs H2O (Solvent properties of water)
Anions (Cl-) surrounded by positive poles of water molecules
Cations (Na+) surrounded by negative poles of water molecules
This keeps the Na+ and Cl- in solution as electrolytes
Hydrophilic “water loving” (Solutes)
Hydrophilic molecules are polar or charged
Polar covalent bonds or ionic bonds
“like” interacting with water
very easily dissolve in water.
Examples: glucose & salts
Hydrophobic “water fearing” (solutes/compounds)
Hydrophobic molecules are non-polar or carry no charge
do not “like” interacting with water
will not dissolve
Examples: fats and oils
Water as a Chemical Reactant
hydrolysis & dehydration reactions
The Heat Capacity of Water
heat capacity = quantity of heat required to raise temperature of a unit mass of substance by 1°C
Water has a high heat capacity, meaning it takes a lot of heat to raise the temperature of water compared to some other liquids
hydrogen bonds between water molecules must be broken, which requires energy (so more heat required)
Water as a Lubricant
Little friction between water molecules, so thin layer of water reduces friction between surfaces
joints and for lining body cavities
Mixture
Colloid
Suspension
Viscosity
Mole
Mixture
= combination of physically blendedelements and/or compounds that are NOTheld together by chemical bonds
Example: The air we breathe is a mixture of O2, H2, N2, & CO2.
three types of liquid mixtures
Solutions
Colloids
Suspensions
Solution
liquid mixture where the solute(minor component) is uniformly distributedwithin the solvent (major component)
Particles are < 1 nm and cannot be seen with the naked eye
Colloid
a solution where the solutes arelarge enough to scatter light
Particle size are 1 nm to 1000 nm
An example is fog
Suspension
a mixture of solutes within asolutionwhich settle out overa period of time into theirdifferent components
Particle size is > 1000 nm
suspension example
(blood)
If left over time, the cells in blood will settle into their components (plasma/RBC/WBC/platelets)
Viscosity
fluid’s resistance toflow
“thicker” a substance, the more viscous it is and therefore the slower itflows(more internal friction)
Concentration of Solutions (Molarity)
of molecules in a given volume of solution
mass per volume percentage
Molarity:
units of moles per liter (mol/L)
1 Mole of atoms = 6.022 x 10^23 (Avogadro’s number)
molarity & moles
one mole of any given element always contains the same number of atoms as one mole of another element
a mole is equal to the quantity with a weight (in grams) equal to an element’s atomic weight (mass?)
e.g.
12 grams of carbon = 1 mole of carbon (6.022 x 10^23)
1.01 grams of hydrogen = 1 mole of hydrogen
4 grams of helium = 1 mole of helium
etc.
MOLARITY = number of moles of solute per liter of solution
Molar solution (molarity)
= a solution with 1 mol of substance dissolved in 1 L of solvent (error, should be SOLUTION, not solvent)
MOLARITY = number of moles of solute per liter of solution
A molar solution of NaCl would have:
1 mol of NaCl per liter of water (1 mol/L)
= 6.022 x 1023 NaCl molecules per liter of water (1 mol/L)
= 58.44 g of NaCl per liter of water (1 mol/L)
acid/base
Water (H2O) can dissociate into hydrogen ions (H+) and hydroxide ions (OH-)
Hydrogen ions (H+):
is what makes solutions acidic
reactive in solution
can break chemical bonds and disrupt cell and tissue function
pH scale
The scale ranges from 0 to 14 –> measures concentration of H+ ions
pH 0 = 10^0 (1) mol/L (of H+)
pH 1 = 10^-1 (0.1) mol/L (of H+)
Acidic: below 7
Contains more H+ than OH-
Neutral: 7
Contains equal H+ and OH-
Basic: above 7
Contains more OH- than H+
pH of blood
the pH of blood:
7.35 to 7.45
7.35–7.45
Outside this range damages cells and tissues by:
1) Breaking chemical bonds
2) Changing shapes of proteins
3) Altering cellular functions
acidosis and alkalosis
Acidosis = below 7.35 blood pH
Alkalosis = above 7.45 blood pH
death = below 7 blood pH
death = above 7.8 blood pH
Acid
solute that releases H+ ion (I.e. PROTON DONOR)
STRONG ACID:
HCl (Hydrochloric Acid)
Base
solute that removes H+ ion
(I.e. PROTON ACCEPTOR)
(May also release Hydroxide Ion – OH-)
STRONG BASE:
Sodium Hydroxide (NaOH)
Weak Acid & Weak Base
Do not dissociate completely
E.g. Carbonic Acid (H2CO3 —> H+ + HCO3 -)
Salt
inorganic compound (No Carbon/Hydrogen)
is composed of any CATION (except H+) and any ANION (except hydroxide, OH-)
Held together by ionic bonds
dissociate in water and release electrolytes
Neutralizing Acid + Base to create Salt + Water
Acid + Base neutralize to create Salt + Water
H+ & OH- form H2O
remaining molecules (ions) join and form a Salt
example of neutralization reaction
Hydrochloric Acid + Sodium Hydroxide = Water + Sodium Chloride
HCl + NaOH = H2O + NaCl
Buffer Systems in body
1) Carbonic acid –Bicarbonate System
2) Phosphate Buffer System
3) Proteins
1) Carbonic acid –Bicarbonate System
CO2 + Water <—> Carbonic Acid (H2CO3) <—> H+ + Bicarbonate Ion (HCO3)
Bicarbonate ions (HCO3 -) act as weak bases and carbonic acid (H2CO3) acts as a weak acid
20:1 ratio of Bicarbonate ions to carbonic acid in the blood @ normal pH
Carbonic acid levels controlled by the expiration of CO2
bicarbonate is controlled by renal system
respiratory alkalosis vs respiratory acidosis
hyperventilating = Alkalosis
not breathing (hypoventilation) = Acidosis
2) Phosphate Buffer System
Dihydrogen Phosphate = Weak Acid
Monohydrogen Phosphate = Weak Base
H+ + Monohydrogen phospate
—> Dihydrogen phosphate
—> H+ + Monohydrogen phosphate
3) Proteins (as buffers)
E.g. Albumin in plasma
Hemoglobin in RBC
Amine group of Amino Acids = Weak Base (buffers acids)
Carboxyl group of Amino Acids = Weak Acid (buffers bases)
Albumin = white of egg in Latin
Hemo-globin = blood + little ball (Latin)
organic chemistry
study of carbon containing compounds (molecules)
larger and more complex than inorganic molecules/compounds
what do organic molecules always contain
CHON-SP
always contain Carbon
Almost always contain Hydrogen
often oxygen and nitrogen
CHON*
sometimes phosphorus and sulfur
CHON-SP
what type of bonds do organic molecules use?
Covalent bonds
how much of body mass is carbon?
Carbon is about 19% (18.5%) of body mass
CHON
Carbon atomic mass
12.011 amu (daltons)
what backbone does Carbon form in organic molecules?
Carbon backbone chain/ring of all organic molecules/compounds
4 Major categories of organic molecules
1) Carbohydrates CHOs
2) Lipids
3) Proteins (via amino acids)
4) Nucleic acids (RNA, DNA)
*ATP – Adenosine triphosphate
–> The “5th” category, but traditionally grouped with nucleic acids because of adenine group
3 shape types of Carbon (organic) compounds (backbone)
1) straight
2) branched
3) ring
1) straight carbon compounds
e.g.
methane, propane, simple fatty acids
2) branched carbon compounds
e.g.
glycogen
3) ringed carbon compounds
e.g.
glucose
pentose, hexose
a type of carbon compound (hydro…)
hydrocarbons
ONLY CONSIST OF CARBON AND HYDROGEN
E.g.
Methane, propane, butane
the structure of carbon compounds (2 group types)
consist of:
A) Functional group
B) Variable group
7 functional groups
Variable group attaches to functional group
the 7 major functional groups of carbon compounds
HSCCEPA
holy shit credit card Environmental Protection Agency
1) Hydroxyl (contains OH)
2) Sulfhydryl (contain SH)
3) Carbonyl (contains C=O)
4) Carboxyl (contains COOH)
5) Ester
6) Phosphate (contains PO4)
7) Amino (contains NH2)
1) Hydroxyl group
-OH
commonly found in organic compounds, such as alcohols and carbohydrates
polar and hydrophilic
participate in dehydration synthesis and hydrolysis reactions
2) Sulfhydryl group
-SH
found as a part of some amino acids
presence of a sulfhydryl group can affect the chemical and physical properties of a molecule, such as its reactivity and ability to form disulfide bonds
3) Carbonyl group
C=O
composed of acarbonatomdouble-bondedto anoxygenatom
Can be either a KETONE or an ALDEHYDE (shown below)
ketones are breakdown products of fats & proteins
4) Carboxyl group
COOH
Make up a part of every amino acid
Can act as an acid (e.g. Carboxylic acid)
5) Ester group
R-CO-OR
found in fats, oils, and triglycerides
6) Phosphate group
-PO4
key component of ATP and other high energy bonds
key component of DNA/RNA
7) Amino group
-NH2
Make up a part of every amino acid
Can act as a base to form –NH3+
monomer vs polymer
monomer = smallest unit of organic molecule
polymer = multiple monomers
created via DEHYDRATION SYNTHESIS
E.g.
protein = polymer
amino acid = monomer
polysaccharide = polymer
monosaccharide = monomer
(GLYCOGEN vs GLUCOSE)
*protein/glycogen via dehydration synthesis
isomers
molecules with same formula but different structure
different reactive properties
C6H12O6 = glucose, but also = fructose, depending on arrangement
glucose/fructose are both MONOMERS,
both have RING shape,
but… FUNCTIONAL GROUPS are arranged differently
isomers random example
pentane, iso-pentane, neo-pentane
carbohydrates
CHO ratio of 1:2:1
hydrated carbons CH2O
most have “-ose” suffix
e.g.
glucose, fructose, mannose, ribose
majority used for energy, ATP production
can be stored as glycogen,
or converted to lipids and stored as adipose tissue
3 classifications of carbohydrates
1) Monosaccharides
2) Disaccharides
3) Polysaccharides
1) Monosaccharides
Monomer of carbohydrates
e.g.
glucose (blood sugar)
fructose
galactose (milk)
deoxyribose
ribose
majority either PENTOSE or HEXOSE ring structure
pentose = 5 carbon ring
hexose = 6 carbon ring
pentose vs hexose
common pentoses:
e.g.
deoxyribose
ribose
common hexoses:
e.g.
glucose
fructose
galactose
2) Disaccharides
2 monosaccharides
via dehydration synthesis
removes H2O
e.g.
Sucrose, leaves C12H22O11
(one H2O removed)
disaccharides e.g.
Sucrose
Lactose
Maltose
disaccharides examples
Sucrose = glucose + fructose
lactose = glucose + galactose
maltose = glucose + glucose
what happens to disaccharides during digestion
dehydration synthesis reaction is reversed
HYDROLYSIS occurs:
H2O is added, and product is 2 Monosaccharides
lactose intolerance
reduced lactase enzyme
body cannot break down lactose (disaccharide)
lactase supplements, or dairy removal
3) Polysaccharides
up to thousands of Monosaccharides
complex carbohydrates
e.g.
glycogen
starches
cellulose
glycogen, where is it stored
skeletal muscles and liver
broken down via catabolic reactions when energy is needed
what is the term for breaking down of glycogen?
What is the term for formation of glycogen?
The term for breaking down of glucose?
The term for glucose being made from sources such as fats/proteins?
Glycogenolysis
glycogenesis
glycolysis
gluconeogenesis
what hormones control glycogen breakdown and synthesis?
Glucagon, Insulin
starches
Polysaccharide formed from glucose found in plants (e.g. potatoes and wheat)
Major carbohydrates in the diet
Broken down into glucose during digestion via hydrolysis
cellulose
Polysaccharide of glucose
Stored in plants, indigestible in humans, but helps with bowel movements, and cleansing of the colon (fiber)
People who consume large amounts of green leafy vegetables have a lower incidence of colon cancer
the different types of lipids
1) Fatty acids
2) Triglycerides (fats and oils)
3) Phospholipids
4) Steroids
5) Eicosanoids
Lipids
CHO ratio:
1:2:MUCH LESS
lipids function
energy storage
cell signaling
membrane structure
and more
how much of body is lipids
Lipids comprise up to 25% of body mass
why are lipids nonpolar
LOW OXYGEN
HYDROPHOBIC
float on surface
when can lipids dissolve in water?
small lipids attached to proteins may dissolve in water
E.g.
Glyco-lipids (sugar fat)
Lipo-proteins (fat protein)
1) Fatty acids
Fatty acids are simplest of lipids
Consists of a carboxyl group and a hydrocarbon chain
Fatty acids are used to make phospholipids and triglycerides
They can undergo beta-oxidation to make ATP when needed
saturated vs unsatured fatty acids
Saturated vs Unsaturated Fatty Acids
If the hydrocarbon chain has only single covalent bonds, it’s termed saturated (i.e. it’s completely saturated with hydrogen)
If there is 1 or more double covalent bond, it’s called unsaturated (i.e. it’s only partially saturated with hydrogen)
A saturated fat is a triglyceride rich in saturated fatty acids (more with TGs)
Cis vs Trans fatty acids (unsaturated)
Cis fatty acids have hydrogen atoms on the same side as the double bond
Trans fatty acids have hydrogen atoms on the opposite side of the double bond
Only occur in small amounts in nature
Solid at room temp, created to replace saturated fats
A trans fat is a triglyceride rich in trans fatty acids (more with TGs)
hydrogenation and trans fatty acids
Cis fatty acids can be converted to trans form through an industrial process calledhydrogenation (adding hydrogens to vegetable oils)
Hydrogenation increases the shelf life of these products and makes vegetable oils solid
However, it hasbeen shown to elevate the risk of cardiovascular disease by increasingLDLs and decreasingHDLs
Monounsaturated vs Polyunsaturated Fatty acids
Monounsaturated
1 double covalent bond = 1 kink
Polyunsaturated
More than 1 double covalent bond = 2 or more kinks
A polyunsaturated fat is a triglyceride rich in polyunsaturated fatty acids (more with TGs)
essential vs non-essential fatty acids (FAs)
Essential Fatty Acids (EFAs)
Need to be obtained from the diet
Non-Essential Fatty Acids
Can be made in the body
what are essential fatty acids?
Polyunsaturated fatty acids (PUFAs) that must be derived from our diets
Our bodies cannot synthesize them
In the diet, these are usually a part of a triglyceride
two categories of Essential Fatty Acids (EFAs)
Omega-3 fatty acids
Omega-6 fatty acids
omega 3 fatty acids
First double bond is found on the third carbon from the methyl end
There are 3 forms of omega-3 fatty acids:
1) Alpha linolenic acid (ALA)
2) Eicosapentaenoic acid (EPA)
3) Docosahexaenoic acid (DHA)
3 Omega 3 fatty acids, where are they found
Alpha linolenic acid (ALA) found in walnuts, flaxseed oil, chia seeds, and hemp
Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) is found in cold-water fatty fish like salmon
Seaweed, nori, spirulina, and chlorellaare only plants with EPA and DHA
omega 6 fatty acids
First double bond is found on the sixth carbon from the methyl end
There are 4 forms of omega-6 fatty acids, two of which you will likely discuss in nutrition
E.g.
Linoleic acid (LA)
Arachidonic acid (ARA)
omega 6 fatty acids, where?
Omega-6 Fatty Acids
Found in high amounts in:
Vegetable oils
Soybeans
Nuts and seeds
Eggs
Non-essential fatty acids
These make up the majority of fatty acids (plant oils and animal fats)
They can be made by our bodies
Examples:
Oleic acid (olive oil, nuts, seeds)
Palmitic acid (animal products)
Stearic acid (Animal products)
omega 6 just as important as omega 3
2) TRIGLYCERIDES
1 glycerol molecule with 3 FA (fatty acids) chains
formed by dehydration synthesis
how is fat stored in body?
Fats are stored in the body as triglycerides in adipocytes (fat cells)
Virtually unlimited capacity to store adipose tissue in various locations throughout the body
Abdomen
Buttocks
Breasts
Thighs
Face
etc
more about triglycerides
In the diet, 95% of fats are in the form of triglycerides
triglycerides make up oils and fats
Oils
triglycerides that are liquid at room temp
tend to be more unsaturated
Fats
triglycerides that are solid at room temp
tend to be more saturated
saturated fats
Saturated Fats
Contains FAs of single covalent bonds only (saturated fatty acids)
Found in meats, dairy products (milk, cheese, butter) but also in some plants (coconut & palm oil)
monounsaturated fats
Monounsaturated Fats
Contains FAs of with one double bond only
Found in olive, canola, peanut, and most other nut oils, avocados
“Healthy” fat
polyunsaturated fats
Polyunsaturated Fats (PUFAs)
Contains FAs of with more than one double bond
These are omega-3s and omega-6s
Found in sunflower, corn, soybean, and fish oils
“Healthy” fat
how triglycerides are broken down
Triglycerides are broken down in the digestive tract or in the body (adipocytes) into glycerol and free fatty acids via hydrolysis
Free fatty acids can go to the mitochondria and be used to created ATP (Gluconeogenesis?)
3) Phospholipids
2 instead of 3 fatty acids
phosphate attached to glycerol
Cell Membrane
amphipathic (polar and non polar components)
phosphate head = polar (hydrophilic)
fatty acid tails = non polar (hydrophobic)
(phospho)lipid bilayer
cell membranes
selectively permeable membrane
Molecules that are smaller and non-polar, such as fats, may pass through the membrane easily
Molecules that are polar/hydrophilic may NOT pass through very easily
Examples:
Small nonpolar molecules, such as O2 and CO2, are soluble in the lipid bilayer and therefore can readily cross cell membranes
Glucose can not pass easily (too big)
Proteins usually carry a charge and need a carrier to get through the membrane
4) Steroids
4 rings of carbon
most common steroid in body
cholesterol
other steroids made from cholesterol
functions of steroids (e.g. cholesterol)
regulating metabolism
maintaining the structural integrity of cell membranes
acting as signaling molecules (precursor to hormones and vitamin D)
examples of steroids in body
Hormones:
Estrogen, testosterone, cortisol
Vitamin D
Required for normal bone growth (is a hormone)
Bile salts
produced by the liver and stored in the gall bladder (“emulsify” fats)
how do steroids (e.g. cholesterol) aid the plasma membrane?
Modulates fluidity so membrane is flexible
Maintains structural integrity, strengthening the membrane and making it resistant to temperature changes
Aids in cell signaling
5) Eicosanoids
oxidized derivative of 20-carbon polyunsaturated fatty acids – usually arachidonic acid (Omega 6)
types of eicosanoids
Prostaglandins (PGs)
Inflammatory responses, bronchiole dilation, body temperature, blood clots
Leukotrienes (LTs)
Allergic & inflammatory responses
Prostaglandins (PGs)
Pain perception
Fever production
Blood clotting
Regulates inflammatory response
Medications like aspirin, ibuprofen (Advil), and acetaminophen (Tylenol) all block PG to some degree
Leukotrienes (LTs)
Made and released from white blood cells (leukocytes) of the immune system
Coordinate and regulate the immune response
6) OTHER LIPIDS (including vit A, E, K, and lipoproteins)
Carotenes
Precursor to vit A (pigments of rods and cones in the eyes)
Found in beets, carrots, & tomatoes.
Vitamin E
Tissue healing and powerful antioxidant (neutralizes free radicals)
Vitamin K
helps in the formation of blood clots
Lipoproteins
Carry cholesterol and triglycerides around the body
Lipoproteins
transport triglycerides and cholesterols
water soluble
5 types of lipoproteins
High-density lipoprotein (HDL)*
Low-density lipoprotein (LDL)*
Very low-density lipoprotein (VLDL)*
Intermediate-density lipoprotein (IDL)
Chylomicrons
*Made in the liver
which lipoproteins are made in liver
HDL
LDL
VLDL
HDL
High-density lipoprotein (HDL)
High density because they have the highest proportion of protein
Considered “good cholesterol” because takes cholesterol and TGs to the liver to be removed from the system
High levels of HDL reduce your risk of cardiovascular (heart) disease.
LDL
Low-density lipoprotein (LDL)
Low density because they have the lowest proportion of protein
Considered “bad cholesterol” because takes cholesterol and TGs to cells
If LDL levels are too high, can be deposited in arteries and form plaques
(atherosclerosis)
VLDL
like LDL but more for TGs than cholesterol
IDL
Intermediate-density lipoproteins (IDL)
created when VLDLs give up their fatty acids
They’re then either removed by your liver or converted into LDL
chylomicrons
The largest lipoproteins
Made in enterocytes of the small intestine
Transport dietary fats through the blood
proteins percent of body
Make up 12-18% of body mass
6 types of proteins
Structural
Regulatory
Contractile
Immunological
Transport
Catalytic
1) structural proteins
formation/framework of cells
keratin, collagen
2) regulatory protein
hormone
insulin
glucagon
3) contractile protein
actin, myosin
filaments in muscle fibres
4) immune proteins
form immune cells like WBC
antibodies
5) Transport proteins
RBC
e.g. Hemoglobin, carry O2, and CO2
cell membranes
6) catalyst proteins
enzymes
accelerate chemical reactions, lower activation energy
monomers of proteins
amino acids
structure of amino acids
carboxyl group (acid)
amine group (base)
side chain (unique to each amino acid)
how many amino acids
20 amino acids
11 = Non-essential
9 = essential
peptide bond
B/W THE
N of the amino group (NH2) (base)
AND THE
C of the carboxyl group (COOH) (acid)
peptide bond types
2 amino acids, 1 peptide bond = dipeptide
3 amino acids, 2 peptide bonds = tripeptide
10-2000 or more peptides = polypeptide (a protein)
how peptide bonds are formed/broken
formed via dehydration synthesis
broken via hydrolysis
4 levels of protein structure
primary
secondary
tertiary
quaternary
1) primary level of structure of protein
amino acid sequence (genetically determined)
Determines the protein and determines the next three structures
2) secondary level of structure of protein
repeated twisting of neighboring amino acids in the polypeptide chains
either or both:
alpha helices
beta pleated sheets
3) tertiary level of structure of protein
3-D shape of the polypeptide chain. Secondary structures folding upon themselves
4) quaternary level of structure of protein
Arrangement of 2 or more polypeptide chains
e.g. hemoglobin
Hemoglobin:
Protein in RBCs
Carries oxygen and CO2
protein denaturation
Term used to describe the altering or destruction of the protein structure, usually in abnormal states caused by pathological conditions
what causes protein denaturation? examples
Heat (frying an egg)
Abnormal pH (HCl in stomach)
Chemical exposure
Genetic mutations
Enzymes (Catalyst proteins)
decrease activation energy
Consist of two portions
Apoenzyme: inactive protein portion
Cofactor: active non-protein portion
Usually vitamins, minerals, or other
enzyme vs substrate
substrate – material enzyme acts on
substrate enters active site of enzyme
enzymes controlled by cell environment
E.g.
Pepsinogen only converts to pepsin in presence of HCl
NUCLEIC ACIDS
CHON-P
(Phosphorus) – no sulfur
1) contain pentose sugar (RIBOSE/DEOXYRIBOSE)
2) contain Nitrogenous base
3) contain phosphate group (PO4)
Nucleotide
vs
Nucleoside
basic structural unit of DNA/RNA:
1) contain pentose sugar (RIBOSE/DEOXYRIBOSE)
2) contain Nitrogenous base
3) contain phosphate group (PO4)
also structural unit of DNA/RNA
1) contain pentose sugar (RIBOSE/DEOXYRIBOSE)
2) contain Nitrogenous base
3) DOESNT CONTAIN PHOSPHATE GROUP (PO4)
NUCLEOSIDE = precursor for nucleotide
DNA vs RNA
DNA has 2-deoxyribose sugar
RNA has ribose sugar
the 5 Nitrogenous bases
PURINES: (PURE AS GOLD)
Adenine
Guanine
PYRAMIDINES: (CUT)
Cytosine
Uracil
Thymine
what does DNA form
DNA forms genetic material (chromosomes)
ALMOST ALL CELLS:
Not in RBC, and platelets
Present inside nucleus
Consists of “Genes”
DNA: Structure
Formed by nucleotides:
1) 2-deoxyribose (pentose SUGAR)
2) Nitrogenous Base
(A/G, C/T –NOT URACIL)
3) Phosphate group
DNA: Shape
double stranded helix
backbone via alternating
A) pentose SUGAR
and B) PHOSPHATE group
DNA: Shape (how do the nitrogenous bases interact?)
nitrogenous bases attach to pentose sugar (2-deoxyribose)
Guanine only pairs with Cytosine
Adenine only pairs with Thymine
DNA: Polarity
one end different from other end
polarity
5 prime end is phosphate end
3 prime end is pentose end
strands are antiparallel to each other
Genes vs DNA
Genes = segments of DNA molecules
encode for amino acid combos
combo of Amino acids is determined by sequence of NUCLEOTIDES
arrangement of Amino Acids makes specific protein
proteins group together and are passed down from one generation to next
RNA
DNA produces RNA
TRANSCRIPTION = making RNA
mRNA makes proteins = TRANSLATION
RNA does not stay in nucleus
When RNA is made, it leaves nucleus
goes to cytoplasm
what is Translation
mRNA makes proteins = TRANSLATION
what is transcription
TRANSCRIPTION = RNA made from DNA
what is mRNA
messenger RNA:
forms template for protein translation
DNA -> mRNA -> protein
what is tRNA
amino acid translation
transfer RNA
–> transfer amino acids
rRNA
ribosomal RNA
mRNA translation
forms ribosomes (site of translation)
RNA: structure
ALSO formed by NUCLEOTIDES
1) Ribose (pentose sugar)
2) Nitrogenous base
(A, U, C, G – NOT THYMINE)
3) Phosphate group
RNA strand
single strand instead of double strand
No thymine
Uracil instead
still alternating phosphate & pentose sugar for backbone
ribose instead of deoxyribose
ATP
similar structure to DNA/RNA
Not genetic material
used for energy around body
via breakdown of lipids/sugars/proteins
ATP: structure
1) ADENINE (Purine – same as Adenine in RNA/DNA)
2) Ribose sugar
3) 3 (Tri) phosphates
I.e.
A pentose sugar,
a nitrogenous base (Adenine)
and 3 phosphates
why are bonds between phosphates high energy
phosphate large
negatively charged oxygens in close proximity
energy is required to hold structure
energy is released when structure is released
how is energy derived from ATP
bond b/w phosphates is broken – energy released
ATP converted to ADP
Exergonic reaction
VIA enzyme ATPase
how does ADP turn into ATP (reverse)
when body has enough energy P is added to ADP and becomes ATP
5 prime vs 3 prime end
5 prime end is phosphate end
3 prime end is pentose end
majority of catabolic reactions are done via…
hydrolysis
at equilibrium, rate of reaction of ____ reactions is the same
reversible reactions
