Intro to macromolecules (2) Flashcards
macromolecules
huge, highly organized molecules –> structure & function in cell
which macromolecules are polymers?
DNA, NAs & Carbs
not lipids
polymers
composed of many low molecular wt building blocks (monomers)
lipids
small, diverse organic molecules that are insoluble in water but soluble in non polar organic liquids
describe the polarity of parts of a lipid
carbon chain - hydrophobic
carboxyl head - hydrophilic
micelle
arrangement of lipids in water
hydrophilic region points towards water
hydrophobic region points away form water
function of lipids
source of E in diet store E in body some hormones (ex: steroids) vitamins structure of membranes (phospholipids )
What are the building blocks of phospholipids?
FAs
FA structure
unbranched hydrocarbon chains with a carboxyl gap at one end
amphiphatic
hydrophilic & hydrophobic properties found within the same molecule
what form micelles?
FAs
what is a FAs role in milk?
micelles create white colour
what is the general formula of carbs?
(CH2O)n
monoscharrides
simple sugar, E & carbon source
polysaccharides
chains for monosaccharide units
what molecules are found in polysaccharides? & what is their role
glycogen
starch
cellulose
role: E storing
glycogen
polysaccharide, E storing
found in animal cells (liver & muscle), branched
starch
polysaccharide, E storing
found in plant cells
helix, mixed of branched & unbranched
why can’t humans digest cellulose?
cannot digest monomers , bonds differ from starch
cellulose
polysaccharide, E storing
insoluble, rigid structural polymer
makes up cell walls –> enables growth in plants
what is an ex of animals breaking down cellulose?
cows & termites have symbiotic bacteria & protozoa that digest cellulose
they contain cellulase
what are the nucleotide units?
nitrogenous base (1-2 ringed with N) pentose sugar (5 C sugar) phosphate grp --> connect sugars via backbone
how do nucleotides attach?
through the sugar phosphate backbone
what are the functions of nucleotides?
units that form DNA & RNA
2nd messengers in cell singling (ex: cAMP)
E transfer for metabolism by cleaving phosphate grps (ATP) or act as co-enzymes (NAD)
co-enzyme
non PRO compounds needed for enzyme rxn
NAD
nicotinamide adenine dinucleotide
what are the purines?
A & G
what are the pyrimidines?
T & C
what provides the diversity of PROs?
folding
what are the functions of PROs? (9)
Enzymes PRO catalysts
Structural elements (ex: tubulin)
Contractile elements (ex: myosin motor PRO)
Control activity of genes, gene expression (ex: transcription factors)
Transport material across membranes (ex: glucose transporter, open & close channels)
carrier (ex: hemoglobin)
hormones (ex: insulin)
antibodies
what are the classification of R grps?
polar uncharged
polar charged
non polar
R grps with unique properties
What is the primary structure of PROs?
sequence of AAs
What is the secondary structure of PROs?
beta sheets or alpha helices
What is the teritary structure of PROs?
way regions of the secondary structure are oriented with respect to each other
result of side chain interactions
What are the bonds that contribute to tertiary & quaternary structure?
H bonds
hydrophobic bonds (inside PRO)
ionic bonds
disulphide bonds
disulphide bonds
covalent bond b/w cytosine
What is the quaternary structure of PROs?
multimeric PROs contain several polypeptide chains
what are the methods for determining tertiary & quaternary structure?
X-ray crystallography
nuclear magnetic resonance
what are ways that a PRO’s structure determines its function?
Change in structure changes function
Cells routinely modify PRO structures to regulate activities
Mutations can damage function
A changed AA can alter a PRO’s ability to interact with other molecules
