Macromolecule Test

elements

composed of only 1 type of atom

nucleus

the center of the atom with protons and neutrons

protons

positively charged and have a mass = 1

• number of these determines what the element is

neutrons

no charge and are neutral; have a mass = 1

electrons

move in orbits around the nucleus of the atom in relatively distinct areas called energy levels

• farther from the center, the more energy

• negatively charged

• can gain and lose energy by moving between energy levels

atomic number

the number of protons the atom has. It is the number of protons an element has which determines what element it is

mass number

the total mass of an atom in AMU

• same as number of protons + neutrons

• this can change without changing the identity of the element

isotopes

atoms having the same atomic numbers and different mass numbers

• same number of protons with different number of neutrons

• react chemically the same as the normal form of the element

• frequently radioactive

ion

when an atom has a different number of protons and electrons

ionic bonds

form when 1 atom gives one or more electrons to another atom to complete their outer energy levels

• results in 1 positively charged ion and 1 negatively charged ion

• a weak bond

cation

positive ion

anion

negative ion

covalent bond

form when 2 atoms share one or more electrons between them

• type of strong bond - both atoms holding onto the electrons

nonpolar bonds

form when two atoms share electrons equally

polar bonds

form when two atoms share electrons unequally

molecule

a group of 2 or more atoms held together by covalent bonds

hydrogen bond

positive H atom in 1 water molecule is attracted to a negative O in another

• can occur wherever -OH exists in a larger molecule

• weak bond

Van der Waals Interaction

weak attractive forces that hold non-polar molecules together

• slight, fleeting attractions between atoms and molecules close together

• weakest bond

reactants

substances existing before the reaction

products

substances existing after the reaction

catalysts

substances which speed up the rate of reaction

exergonic

release or give energy

endergonic

take or absorb energy

potential energy

energy of position

kinetic energy

energy of movement

valence shell

where the outermost electrons are located on an atom

electronegativity

refers to the element’s or molecule’s desire to acquire or release electrons

• hydrogen atoms are the least biological element of this

  • oxygen is the most biological element of this

structural formula

show the shape of the molecule

molecular formula

used to tell the elements and number of atoms of each

organic chemistry

the study of carbon compounds

carbon

has 4 valence electrons

• usually forms 4 covalent bonds with other atoms

• allows molecules to branch off in up to four directions

• makes large, complex molecules possible

hydrocarbons

organic molecules consisting of only carbon and hydrogen

• major component of petroleum

• are hydrophobic because the bonds are nonpolar

• store relatively large amount of energy

isomers

compounds that have the same molecular formula, but different structural formulas, therefore different properties

• differ in the covalent arrangement of their atoms

• may differ in the placement of a double bond

geometric isomers

same covalent partnership, differ in spatial arrangement

• due to inflexibility of double bonds, do not allow atoms to rotate about the axis

• the subtle difference in shape can dramatically affect the biological activities of the molecule

enantiomers

mirror images of each other

• differ in spatial arrangement around an asymmetric carbon (a carbon atom bonded to 4 different kinds of atoms or groups of atoms

• each may behave differently in the body

hydroxyl group

• organic compounds containing this are alcohols

• name usually ends in -ol

• hydrophilic - soluble in water

• -OH

Carbonyl group

• a carbon atom joined to an oxygen atom by a double bond

• if it is on the end, its an aldehyde

• anywhere else, its a ketone

• hydorphilic - soluble in water

• C=O

carboxyl group

• an oxygen atom double bonded to a carbon atom that is also bonded to a hydroxyl

• COOH

• compounds containing this are called organic acids

• hydrophilic - soluble in water

• have acidic properties

amino group

• a nitrogen atom bonded to two hydrogen atoms and to the carbon skeleton

• compounds containing this group are aminos

• hydrophilic - soluble in water

• have basic properties

• NH2

sulfhydryl group

• a sulfur atom bonded to an atom of hydrogen

• compounds containing this are thiols

• hydrophilic - soluble in water

• interact to stabilize the structure of a protein

• SH

phosphate group

• a phosphate ion covalently attached by one of its oxygen atoms to the carbon skeleton

• transfers energy between organic molecules

• hydrophilic - soluble in water

• PO4 or PO4H2

Methyl

• CH3

• nonpolar

• not water soluble

• hydrophobic

cohesion

refers to water molecules binding to other water molecules

• made possible because of hydrogen bonds

• allows water to move upward in plants xylem tissues by making water chains

adhesion

refers to water molecules binding to something other than water molecules

• made possible because of hydrogen ponds

surface tension

a measure of how difficult it is to stretch or break the surface of a liquid

heat

a type of energy

• depends on the mass of the substance

specific heat

amount of heat that must be absorbed or lost for 1g of substance to change its temperature by 1 degree C

heat of vaporization

energy required to change 1g of substance from a liquid to a gas

evaporative cooling

water molecules with high kinetic energy evaporate remaining molecules are cooler

ice floats

water expands as it freezes, less dense as a solid, hydrogen bonds in ice keep the molecules far enough apart to make it less dense than liquid water

• allows for insulation of bodies of water

solution

a liquid that is completely homogeneous mixture of two or more substances

solvent

the dissolving agent of a solution

solute

the substance that is dissolved

aqueous solution

solution where water is the solvent

hydrophilic

a substance with an affinity/able to dissolve in water

hydrophobic

a substance that repels water/don’t dissolve

mole

represents an exact number of molecules of a substance in a given mass

molarity

the number of moles per liter of solution

dissociation

refers to water breaking apart into H+ (proton) and an OH- (hydroxide ion)

acid

• when dissolved in water, add H+ to the solution

  • less than 7 on pH scale

base

reduces the hydrogen ion concentration of a solution, work either by accepting hydrogen ions or dissociating to form hydroxide ions

• more than 7 on pH scale

buffer

minimize changes in concentration of H+ and OH- ions in a solution

• normally maintain pH of human blood very close to 7.4

  • work by accepting H+ ions from the solution when they are in excess and donating H+ ions to a solution when they have been depleted

acid precipitation

• mostly sulfur oxides and nitrogen oxides dissolved in rainwater

• come from fossil fuels burned in factories and automobiles

polymers

long molecules made from the building blocks linked by covalent bonds

monomer

the building block to polymers

• connected to form polymers through a condensation reaction or specifically a dehydration synthesis

hydrolysis

polymers are broken down into monomers by adding water

carbohydrates

include sugars and their polymers

• 1:2:1 C:H:O ratio

  • serve as the raw building materials for the other 3 organic molecules

glycosidic linkage

covalent bond between carbohydrate monomers

monosaccharide

single sugar or simple sugar

• glucose, fructose, galactose, etc

• have a carbonyl group and multiple hydroxyl groups

• ranges from 3-7 carbons

disaccharide

double sugar, formed by two monosaccharides bonded together

• sucrose, lactose, maltose

• joined by a glycosidic linkage

polysaccharide

many monosaccharides bonded together

• starch, glycogen, cellulose, chitin

• formed from a few hundred to a few thousand monosaccharides

• serve two main purposes: structure and storage

starch

major storage polysaccharide in plants

• made up of glucose monomers

• source of stored energy

  • humans and other animals hydrolyze the starch in potatoes and grains for a source of energy

glycogen

storage polysaccharide in animals

• stored mainly in the liver and muscle cells

  • reserves only last about 1 day in humans

cellulose

structural component of plant cell walls

• most abundant organic compound on earth

• made up of glucose monomers

• differs from starch in the linkage of glucose monomers

• many animals, including humans, are unable to digest cellulose

chitin

makes up the exoskeletons of arthropods

• hardens with the aid of calcium carbonate

• also found in the cell walls of fungi

sucrose

Glucose + fructose

maltose

glucose + glucose

lactose

glucose + galactose

Lipid

large biological molecules that do not form polymers

• hydrophobic

• consist mostly of hydrocarbons

• composed of a glycerol molecule and 3 fatty acids forming a triglyceride

esther linkage

a covalent bond that holds the fatty acid and the glycerol together

• a carboxyl of the fatty acid paired with a hydroxyl of the glycerol molecule

saturated fats

• no double bonds between the carbons, therefore completely saturated with hydrogens

• include most animal fats

• no open bonds to put any more hydrogen on

• are solid at room temperature

  • a diet rich in saturated fats contributes to the cardiovascular disease, atherosclerosis

unsaturated fats

• have one or more double bonds

• will have a “kink” in its tail where the double bonds occur

• fats from plants and fish

• usually liquid at room temperature

• the kinks caused by double bonds prevent the fats from solidifying

  • can be hydrogenated where they are saturated with hydrogen - synthetic so the body cannot fully process

main functions of lipids

• store energy

• insulation/cushion

• cell membrane

• hormones/steroid

adipose tissue

where humans and other mammals store their fat

• tissues cushion vital organs and insulate the body

phospholipids

have only 2 fatty acid tails instead of three

• a phosphate group attached to the third hydroxyl group of the glycerol

• tails are hydrophobic

• heads are hydrophilic

waxes

made by combining alcohols with unsaturated fats. Such as girls’ lipsticks which also have coloring added

steroid

a carbon skeleton consisting of 4 fused rings

-hormones

proteins

• more than 50% of the dry weight of most cells

• humans have tens of thousands with a specific structure and function

• all are polymers built from the same 20 amino acids

• -ase = enzyme

  • used for structural support, storage, transport of substances, signaling from one part of the organisms to another, movement, defense signaling against foreign substances, enzymes

amino acids

• only 20 different ones

• contain a carboxyl end - this part acts as the acid because it can give off hydrogen

• amine end - end can act as a base by accepting a third hydrogen

• Alpha carbon - the central carbon that holds the molecule together

• R group - most important part, gives each one a different property

peptide bond

covalent bond linking amino acids together to form polypeptides

primary structure

• the unique amino acid sequence

  • a change in this structure can affect a protein’s conformation and ability to function

secondary structure

• segments fo the polypeptide chain repeatedly coil or fold in unique patterns that contribute to the protein’s overall conformation

  • results from the hydrogen bonds at regular intervals along the polypeptide backbone, not the amino acid side chains

tertiary structure

• overall shape of a polypeptide resulting from interactions between side chains (r groups) of the various amino acids

• disulfide bridges help stabilize the proteins folded structure

quaternary structure

• the overall protein structure that results from the aggregation of these polypeptide subunits

  • the association between two or more polypeptides that make up a protein

denaturation

the unraveling of a protein or enzyme causing it not to function

chaperonins

protective structure that allows proteins to fold inside without water being present

nucleotides

monomers of nucleic acids

nucleic acids

• two types - DNA or RNA

• store information

• genetic materia

• blueprint for building proteins

  • transfers information

dna

the genetic material inherited from parent to offspring

• usually consists of hundreds or thousands of genes

• carries the information to make proteins

mRNA

• made from the DNA template

  • travels from the nucleus to the ribosome