B1. molecules & fundamentals of bio

intramolecular forces

attractive forces that act on atoms in a molecule

intermolecular forces

attractive forces that exist between molecules

monomers

single molecules w the capability of polymerizing

polymers

substances made up of many monomers linked tg

polymerization

the continuous bonding of 1 monomer to another, forming a polymer

dehydration (condensation) rxn

polymerization rxn that results in the release of water

hydrolysis rxn

depolymerization rxn which utilizes water to break bonds

carbohydrates

molecules used for fuel & structure

monosaccharides

carbohydrate monomers

common examples of monosaccharides

ribose, fructose, & glucose

disaccharides

2 monosaccharides join tg by a glycosidic bond

polysaccharides

contain multiple monosaccharides held tg in a long polymer by glycosidic bonds

starch

energy storge polysaccharide of glucose monomers used by plants

glycogen

energy storage polysaccharide of glucose monomers held tg & used by animals

cellulose

structural support polysaccharides made of many glucose monomers

amino acids

protein monomers

polymer/ polypeptides (proteins)

strands of many amino acids held tg by peptide bonds

peptide bonds

between the carbonyl group of 1 amino acid & the amino group of another

primary structure

the simple amino acid sequence resulting from mRNA translation

secondary structure

holding patterns of the primary amino acid sequence, including alpha helices & beta pleated sheets

tertiary structure

3D structure resulting from interactions between R groups

hydrophobic interactions

congregation or interaction of non polar R groups

disulfide bonds

covalent bonding between 2 sulfur atoms

additional tertiary interactions

H bonding & ionic bonding between R groups are also possible

quaternary structure

multiple polypeptide chains come tg to form 1 protein

conjugated proteins

composed of amino acids & non proteins components

metalloproteins

proteins which contain a mental ion cofactor

glycoproteins

proteins that contain various carbohydrates

protein denaturation

the loss of protein function & higher order structures

storage

reservoir of amino acids

hormones

signaling molecules that regulate physiological processes

receptors

proteins w in cell membranes that bind to signaling molecules

structure

provide strength & support to tissues

immunity

antibodies that protect against foreign substances

enzymes

regulate the rate of chemical rxns

catalysts

increase rxn rates by decreasing activation energy

transition state

unstable intermediate between reactants & products

enzymes

biological catalysts, most are proteins

active sites

receptor regions on an enzyme that are specific for a substrate

specificity constant

measures enzyme binding efficiency for a specific substrate

induced fit theory

active sites mold to some degree to fit the substrate upon binding

lock & key

outdated theory suggesting active sites are rigid & substrates are shape perfectly to fit w in them

ribozymes

RNA molecules that are capable of acting as enzymes

cofactor

non protein molecule that helps enzymes function

coenzyme

organic cofactor such as vitamins

holoenzyme

complex formed when an enzyme binds its cofactor

apoenzyme

enzyme w out a bound cofactor

prosthetic groups

cofactors that are tightly or covalently bound to their enzyme

phosphase

cleavage of a phosphate group off of substrate molecule

kinase

indirectly adds a phosphate group to a substrate molecule

active site

receptor region that’s specific for the desired rxn substrate

allosteric site

substrate binding location that’s separate from the active site

competitive inhibitor

directly competes w rxn substitutes for an enzyme active site

competitive inhibition

competition between inhibitor & enzyme may cause rxn rate to decrease as inhibitor occupies the active site

noncompetitive inhibitor

binds the enzyme’s allosteric site

noncompetitive inhibition

altered active site decreases enzyme-substrate binding

saturation

when all enzyme active site are occupied

Michaelis constant

substrate concentration required to reach half of the max velocity

feedback loops

describe how the product of a rxn affects the rate of the rxn itself

negative feedback loop

rxn products will slow or inhibit the original rxn

positive feedback loop

rxn products will active or increase the original rxn

lipid contents

CHO

fatty acid tails

long hydrocarbon tails w hydrophobic properties

hydrophobic

repels water

hydrophilic

attracts water

lipophilic

attracts lipids

amphipathic

molecule w hydro philic/phobic parts & love lipids

saturated fatty acid

hydrocarbon chain w out any double bonds

unsaturated fatty acid

hydrocarbon chain w double bonds

triglyceride (triacylglycerol)

lipid type containing a glycerol backbone & 3 fatty acids

glycerol backbone

3 carbons that serve as anchors for the fatty acid chains

phospholipids

composed of glycerol backbone, 1 phosphate group, & 2 fatty acid tails

amphipathic phospholipid

phosphate “head group” is polar & hydrophilic while the fatty acids are non polar & hydrophobic

cholesterol

amphipathic lipid component of cell membrane

lipoproteins

round complex of lipids & proteins that carry lipophilic (hydrophobic) molecules through the blood

waxes

simple lipids w long fatty acid chains connected to alcohols

carotenoids

lipid derivatives containing long carbon chains conjugated double bonds that function mainly as pigments

sphingolipids

lipids w a backbone containing aliphatic (non-aromatic) amino alcohols

glycolipids

lipids found in plasma membranes w carbohydrate groups bound rather than a phosphate group

nucleic acids

diverse molecule class composed of sugar monomers

nucleoside

made of ribose or deoxyribose sugar & 1 nitrogenous base

nucleotide

made of 1 ribose or deoxyribose sugar, 1 nitrogenous base, & phosphates

RNA

molecule containing ribose sugar nucleotides that is typically single stranded

DNA

antiparallel double helix molecule containing deoxyribose sugars

sugar-phosphate backbone

structural chain of altering sugars & phosphates held tg by phosphodiester bonds

phosphodiester bonds

condensation rxn used to link nucleotides tg

nucleic acid polymerization

nucleic acids elongate as nucleoside triphosphate are continually added to the free 3’ hydroxyl group of the molecule

mRNA

encodes proteins

tRNA

acts as adapter between mRNA & amino acids

rRNA

forms the ribosome

miRNA

regulates gene expression

dsRNA

store genetic info

primordial earth theory

how early earth provided conditions needed for life

primordial atmosphere

comprised of inorganic compounds creating a reducing environment (low O2)

protobionts

abiotic, lipid capsules that emerged as a precursor to cells

modern cell theory

how cells govern high order iterations of life

central dogma of genetics

info is passed from DNA to RNA proteins; exceptions include reverse transcriptase & prions

endosymbiotic theory

how eukaryotes came to house membrane-bound organelles